llama : add DRY sampler (#9702)

* sampling : add DRY sampler (post-refactor)

* DRY: Trying to fix coauthors, removed unneeded line

* DRY: Fixed redundant code

* DRY: Fixed crash issue due to DRY being in chain but uninitialized

---------

Co-authored-by: l3utterfly <gc.pthzfoldr@gmail.com>
Co-authored-by: pi6am <34464159+pi6am@users.noreply.github.com>

common/arg.cpp

@@ -251,6 +251,9 @@ static bool common_params_parse_ex(int argc, char ** argv, common_params_context
         for (auto & antiprompt : params.antiprompt) {
             string_process_escapes(antiprompt);
         }
+        for (auto & seq_breaker : params.sparams.dry_sequence_breakers) {
+            string_process_escapes(seq_breaker);
+        }
     }
 
     if (!params.kv_overrides.empty()) {
@@ -997,6 +1000,64 @@ common_params_context common_params_parser_init(common_params & params, llama_ex
             params.sparams.penalty_freq = std::stof(value);
         }
     ).set_sparam());
+    add_opt(common_arg(
+        {"--dry-multiplier"}, "N",
+        string_format("set DRY sampling multiplier (default: %.1f, 0.0 = disabled)", (double)params.sparams.dry_multiplier),
+        [](common_params & params, const std::string & value) {
+            params.sparams.dry_multiplier = std::stof(value);
+        }
+    ).set_sparam());
+    add_opt(common_arg(
+        {"--dry-base"}, "N",
+        string_format("set DRY sampling base value (default: %.2f)", (double)params.sparams.dry_base),
+        [](common_params & params, const std::string & value) {
+            float potential_base = std::stof(value);
+            if (potential_base >= 1.0f)
+            {
+                params.sparams.dry_base = potential_base;
+            }
+        }
+    ).set_sparam());
+    add_opt(common_arg(
+        {"--dry-allowed-length"}, "N",
+        string_format("set allowed length for DRY sampling (default: %d)", params.sparams.dry_allowed_length),
+        [](common_params & params, int value) {
+            params.sparams.dry_allowed_length = value;
+        }
+    ).set_sparam());
+    add_opt(common_arg(
+        {"--dry-penalty-last-n"}, "N",
+        string_format("set DRY penalty for the last n tokens (default: %d, 0 = disable, -1 = context size)", params.sparams.dry_penalty_last_n),
+        [](common_params & params, int value) {
+            params.sparams.dry_penalty_last_n = value;
+        }
+    ).set_sparam());
+    add_opt(common_arg(
+        {"--dry-sequence-breaker"}, "STRING",
+        string_format("add sequence breaker for DRY sampling, clearing out default breakers (%s) in the process; use \"none\" to not use any sequence breakers\n",
+            params.sparams.dry_sequence_breakers.empty() ? "none" :
+            std::accumulate(std::next(params.sparams.dry_sequence_breakers.begin()),
+                params.sparams.dry_sequence_breakers.end(),
+                std::string("'") + (params.sparams.dry_sequence_breakers[0] == "\n" ? "\\n" : params.sparams.dry_sequence_breakers[0]) + "'",
+                [](const std::string& a, const std::string& b) {
+                    std::string formatted_b = (b == "\n") ? "\\n" : b;
+                    return a + ", '" + formatted_b + "'";
+                }).c_str()),
+        [](common_params & params, const std::string & value) {
+            static bool defaults_cleared = false;
+
+            if (!defaults_cleared) {
+                params.sparams.dry_sequence_breakers.clear();
+                defaults_cleared = true;
+            }
+
+            if (value == "none") {
+                params.sparams.dry_sequence_breakers.clear();
+            } else {
+                params.sparams.dry_sequence_breakers.emplace_back(value);
+            }
+        }
+    ).set_sparam());
     add_opt(common_arg(
         {"--dynatemp-range"}, "N",
         string_format("dynamic temperature range (default: %.1f, 0.0 = disabled)", (double)params.sparams.dynatemp_range),

common/common.cpp

@@ -2006,6 +2006,10 @@ void yaml_dump_non_result_info(FILE * stream, const common_params & params, cons
     fprintf(stream, "chunks: %d # default: -1 (unlimited)\n", params.n_chunks);
     fprintf(stream, "color: %s # default: false\n", params.use_color ? "true" : "false");
     fprintf(stream, "ctx_size: %d # default: 512\n", params.n_ctx);
+    fprintf(stream, "dry_allowed_length: %d # default: 2\n", sparams.dry_allowed_length);
+    fprintf(stream, "dry_base: %.2f # default: 1.75\n", sparams.dry_base);
+    fprintf(stream, "dry_multiplier: %.1f # default: 0.0\n", sparams.dry_multiplier);
+    fprintf(stream, "dry_penalty_last_n: %d # default: -1 (0 = disable, -1 = context size)\n", sparams.dry_penalty_last_n);
     fprintf(stream, "escape: %s # default: false\n", params.escape ? "true" : "false");
     fprintf(stream, "file: # never logged, see prompt instead. Can still be specified for input.\n");
     fprintf(stream, "frequency_penalty: %f # default: 0.0 \n", sparams.penalty_freq);

common/common.h

@@ -84,14 +84,15 @@ enum llama_example {
 
 enum common_sampler_type {
     COMMON_SAMPLER_TYPE_NONE        = 0,
-    COMMON_SAMPLER_TYPE_TOP_K       = 1,
+    COMMON_SAMPLER_TYPE_DRY         = 1,
-    COMMON_SAMPLER_TYPE_TOP_P       = 2,
+    COMMON_SAMPLER_TYPE_TOP_K       = 2,
-    COMMON_SAMPLER_TYPE_MIN_P       = 3,
+    COMMON_SAMPLER_TYPE_TOP_P       = 3,
-    COMMON_SAMPLER_TYPE_TFS_Z       = 4,
+    COMMON_SAMPLER_TYPE_MIN_P       = 4,
-    COMMON_SAMPLER_TYPE_TYPICAL_P   = 5,
+    COMMON_SAMPLER_TYPE_TFS_Z       = 5,
-    COMMON_SAMPLER_TYPE_TEMPERATURE = 6,
+    COMMON_SAMPLER_TYPE_TYPICAL_P   = 6,
-    COMMON_SAMPLER_TYPE_XTC         = 7,
+    COMMON_SAMPLER_TYPE_TEMPERATURE = 7,
-    COMMON_SAMPLER_TYPE_INFILL      = 8,
+    COMMON_SAMPLER_TYPE_XTC         = 8,
+    COMMON_SAMPLER_TYPE_INFILL      = 9,
 };
 
 // dimensionality reduction methods, used by cvector-generator
@@ -121,6 +122,10 @@ struct common_sampler_params {
     float   penalty_repeat     = 1.00f; // 1.0 = disabled
     float   penalty_freq       = 0.00f; // 0.0 = disabled
     float   penalty_present    = 0.00f; // 0.0 = disabled
+    float   dry_multiplier     = 0.0f;  // 0.0 = disabled;      DRY repetition penalty for tokens extending repetition:
+    float   dry_base           = 1.75f; // 0.0 = disabled;      multiplier * base ^ (length of sequence before token - allowed length)
+    int32_t dry_allowed_length = 2;     // tokens extending repetitions beyond this receive penalty
+    int32_t dry_penalty_last_n = -1;    // how many tokens to scan for repetitions (0 = disable penalty, -1 = context size)
     int32_t mirostat           = 0;     // 0 = disabled, 1 = mirostat, 2 = mirostat 2.0
     float   mirostat_tau       = 5.00f; // target entropy
     float   mirostat_eta       = 0.10f; // learning rate
@@ -128,8 +133,11 @@ struct common_sampler_params {
     bool    ignore_eos         = false;
     bool    no_perf            = false; // disable performance metrics
 
+    std::vector<std::string> dry_sequence_breakers = {"\n", ":", "\"", "*"};     // default sequence breakers for DRY
+
 
     std::vector<enum common_sampler_type> samplers = {
+        COMMON_SAMPLER_TYPE_DRY,
         COMMON_SAMPLER_TYPE_TOP_K,
         COMMON_SAMPLER_TYPE_TFS_Z,
         COMMON_SAMPLER_TYPE_TYPICAL_P,

common/sampling.cpp

@@ -130,9 +130,11 @@ std::string common_sampler_params::print() const {
 
     snprintf(result, sizeof(result),
             "\trepeat_last_n = %d, repeat_penalty = %.3f, frequency_penalty = %.3f, presence_penalty = %.3f\n"
+            "\tdry_multiplier = %.3f, dry_base = %.3f, dry_allowed_length = %d, dry_penalty_last_n = %d\n"
             "\ttop_k = %d, tfs_z = %.3f, top_p = %.3f, min_p = %.3f, xtc_probability = %.3f, xtc_threshold = %.3f, typical_p = %.3f, temp = %.3f\n"
             "\tmirostat = %d, mirostat_lr = %.3f, mirostat_ent = %.3f",
             penalty_last_n, penalty_repeat, penalty_freq, penalty_present,
+            dry_multiplier, dry_base, dry_allowed_length, dry_penalty_last_n,
             top_k, tfs_z, top_p, min_p, xtc_probability, xtc_threshold, typ_p, temp,
             mirostat, mirostat_eta, mirostat_tau);
 
@@ -174,6 +176,17 @@ struct common_sampler * common_sampler_init(const struct llama_model * model, co
     if (params.mirostat == 0) {
         for (const auto & cnstr : params.samplers) {
             switch (cnstr) {
+                    case COMMON_SAMPLER_TYPE_DRY:
+                    {
+                        std::vector<const char*> c_breakers;
+                        c_breakers.reserve(params.dry_sequence_breakers.size());
+                        for (const auto& str : params.dry_sequence_breakers) {
+                            c_breakers.push_back(str.c_str());
+                        }
+
+                        llama_sampler_chain_add(result->chain, llama_sampler_init_dry      (model, params.dry_multiplier, params.dry_base, params.dry_allowed_length, params.dry_penalty_last_n, c_breakers.data(), c_breakers.size()));
+                    }
+                        break;
                 case COMMON_SAMPLER_TYPE_TOP_K:
                     llama_sampler_chain_add(result->chain, llama_sampler_init_top_k    (params.top_k));
                     break;
@@ -358,6 +371,7 @@ std::string common_sampler_prev_str(common_sampler * gsmpl, llama_context * ctx_
 
 char common_sampler_type_to_chr(enum common_sampler_type cnstr) {
     switch (cnstr) {
+        case COMMON_SAMPLER_TYPE_DRY:         return 'd';
         case COMMON_SAMPLER_TYPE_TOP_K:       return 'k';
         case COMMON_SAMPLER_TYPE_TFS_Z:       return 'f';
         case COMMON_SAMPLER_TYPE_TYPICAL_P:   return 'y';
@@ -372,6 +386,7 @@ char common_sampler_type_to_chr(enum common_sampler_type cnstr) {
 
 std::string common_sampler_type_to_str(enum common_sampler_type cnstr) {
     switch (cnstr) {
+        case COMMON_SAMPLER_TYPE_DRY:         return "dry";
         case COMMON_SAMPLER_TYPE_TOP_K:       return "top_k";
         case COMMON_SAMPLER_TYPE_TFS_Z:       return "tfs_z";
         case COMMON_SAMPLER_TYPE_TYPICAL_P:   return "typ_p";
@@ -386,6 +401,7 @@ std::string common_sampler_type_to_str(enum common_sampler_type cnstr) {
 
 std::vector<common_sampler_type> common_sampler_types_from_names(const std::vector<std::string> & names, bool allow_alt_names) {
     std::unordered_map<std::string, common_sampler_type> sampler_canonical_name_map {
+        { "dry",         COMMON_SAMPLER_TYPE_DRY },
         { "top_k",       COMMON_SAMPLER_TYPE_TOP_K },
         { "top_p",       COMMON_SAMPLER_TYPE_TOP_P },
         { "typ_p",       COMMON_SAMPLER_TYPE_TYPICAL_P },
@@ -434,6 +450,7 @@ std::vector<common_sampler_type> common_sampler_types_from_names(const std::vect
 
 std::vector<common_sampler_type> common_sampler_types_from_chars(const std::string & chars) {
     std::unordered_map<char, common_sampler_type> sampler_name_map = {
+        { common_sampler_type_to_chr(COMMON_SAMPLER_TYPE_DRY),         COMMON_SAMPLER_TYPE_DRY },
         { common_sampler_type_to_chr(COMMON_SAMPLER_TYPE_TOP_K),       COMMON_SAMPLER_TYPE_TOP_K },
         { common_sampler_type_to_chr(COMMON_SAMPLER_TYPE_TFS_Z),       COMMON_SAMPLER_TYPE_TFS_Z },
         { common_sampler_type_to_chr(COMMON_SAMPLER_TYPE_TYPICAL_P),   COMMON_SAMPLER_TYPE_TYPICAL_P },

examples/main/README.md

@@ -187,6 +187,30 @@ Use the `--no-penalize-nl` option to disable newline penalization when applying
 
 Example usage: `--repeat-penalty 1.15 --repeat-last-n 128 --no-penalize-nl`
 
+### DRY Repetition Penalty
+
+DRY (Don't Repeat Yourself) sampling is an effective technique for reducing repetition in generated text even across long contexts by penalizing tokens based on their recent usage patterns (original [PR link](https://github.com/oobabooga/text-generation-webui/pull/5677)).
+
+- `--dry-multiplier N`: Set the DRY sampling multiplier (default: 0.0, 0.0 = disabled).
+- `--dry-base N`: Set the DRY sampling base value (default: 1.75).
+- `--dry-allowed-length N`: Set the allowed length for DRY sampling (default: 2).
+- `--dry-penalty-last-n N`: Set DRY penalty for the last n tokens (default: -1, 0 = disable, -1 = context size).
+- `--dry-sequence-breaker STRING`: Add a sequence breaker for DRY sampling. Can be used more than once to add multiple sequence breakers. Using this clears out the default breakers, which consist of: `['\n', ':', '"', '*']`. If the string `"none"` is supplied, no sequence breakers are used.
+
+The `dry-multiplier` option controls the strength of the DRY sampling effect. A value of 0.0 disables DRY sampling, while higher values increase its influence. A typical recommended value is 0.8.
+
+The `dry-base` option sets the base value for the exponential penalty calculation in DRY sampling. Higher values lead to more aggressive penalization of repetitions.
+
+The `dry-allowed-length` option sets the maximum length of repeated sequences that will not be penalized. Repetitions shorter than or equal to this length are not penalized, allowing for natural repetitions of short phrases or common words.
+
+The `dry-penalty-last-n` option controls how many recent tokens to consider when applying the DRY penalty. A value of -1 considers the entire context. Use a positive value to limit the consideration to a specific number of recent tokens.
+
+The `dry-sequence-breaker` option adds a single sequence breaker and can be used more than once to specify multiple sequence breakers. Sequence breakers interrupt sequence matching and break the input into parts where matching can be applied.
+
+DRY sampling provides more nuanced control over text generation, particularly for reducing long-range repetitions and maintaining global coherence.
+
+Example usage: `--dry-multiplier 0.8 --dry-base 1.75 --dry-allowed-length 2 --dry-penalty-last-n -1 --dry-sequence-breaker "—" --dry-sequence-breaker "##"`
+
 ### Top-K Sampling
 
 -   `--top-k N`: Limit the next token selection to the K most probable tokens (default: 40).

examples/server/README.md

@@ -114,6 +114,11 @@ The project is under active development, and we are [looking for feedback and co
 | `--repeat-penalty N` | penalize repeat sequence of tokens (default: 1.0, 1.0 = disabled) |
 | `--presence-penalty N` | repeat alpha presence penalty (default: 0.0, 0.0 = disabled) |
 | `--frequency-penalty N` | repeat alpha frequency penalty (default: 0.0, 0.0 = disabled) |
+| `--dry-multiplier N` | DRY sampling multiplier (default: 0.0, 0.0 = disabled) |
+| `--dry-base N` | DRY sampling base value (default: 1.75) |
+| `--dry-allowed-length N` | allowed length for DRY sampling (default: 2) |
+| `--dry-penalty-last-n N` | DRY penalty for the last n tokens (default: -1, 0 = disable, -1 = context size) |
+| `--dry-sequence-breaker STRING` | add sequence breaker for DRY sampling, clearing out default breakers (`['\n', ':', '"', '*']`) in the process; use `"none"` to not use any sequence breakers
 | `--dynatemp-range N` | dynamic temperature range (default: 0.0, 0.0 = disabled) |
 | `--dynatemp-exp N` | dynamic temperature exponent (default: 1.0) |
 | `--mirostat N` | use Mirostat sampling.<br/>Top K, Nucleus, Tail Free and Locally Typical samplers are ignored if used.<br/>(default: 0, 0 = disabled, 1 = Mirostat, 2 = Mirostat 2.0) |
@@ -369,6 +374,16 @@ node index.js
 
     `frequency_penalty`: Repeat alpha frequency penalty. Default: `0.0`, which is disabled.
 
+    `dry_multiplier`: Set the DRY (Don't Repeat Yourself) repetition penalty multiplier. Default: `0.0`, which is disabled.
+
+    `dry_base`: Set the DRY repetition penalty base value. Default: `1.75`
+
+    `dry_allowed_length`: Tokens that extend repetition beyond this receive exponentially increasing penalty: multiplier * base ^ (length of repeating sequence before token - allowed length). Default: `2`
+
+    `dry_penalty_last_n`: How many tokens to scan for repetitions. Default: `-1`, where `0` is disabled and `-1` is context size.
+
+    `dry_sequence_breakers`: Specify an array of sequence breakers for DRY sampling. Only a JSON array of strings is accepted. Default: `['\n', ':', '"', '*']`
+
     `mirostat`: Enable Mirostat sampling, controlling perplexity during text generation. Default: `0`, where `0` is disabled, `1` is Mirostat, and `2` is Mirostat 2.0.
 
     `mirostat_tau`: Set the Mirostat target entropy, parameter tau. Default: `5.0`

examples/server/public/index-new.html

@@ -40,6 +40,10 @@
       repeat_last_n: 0, // 0 = disable penalty, -1 = context size
       repeat_penalty: 1.0, // 1.0 = disabled
       penalize_nl: false, // true only useful for infinite completion
+      dry_multiplier: 0.0, // 0.0 = disabled, 0.8 works well
+      dry_base: 1.75,     // 0.0 = disabled
+      dry_allowed_length: 2, // tokens extending repetitions beyond this receive penalty, 2 works well
+      dry_penalty_last_n: -1, // how many tokens to scan for repetitions (0 = disable penalty, -1 = context size)
       top_k: 0, // <= 0 to use vocab size
       top_p: 1.0, // 1.0 = disabled
       min_p: 0.05, // 0 = disabled; recommended for non-english: ~ 0.4
@@ -833,13 +837,17 @@ return html`
         <fieldset class="params">
           ${IntField({ label: "Top-K", title: "Limits the selection of the next token to the K most probable tokens. 1 means no randomness = greedy sampling. If set to 0, it means the entire vocabulary size is considered.", max: 100, min: 0, step: 1, name: "top_k", value: params.value.top_k })}
           ${IntField({ label: "Penalize Last N", title: "The last n tokens that are taken into account to penalise repetitions. A value of 0 means that this function is deactivated and -1 means that the entire size of the context is taken into account.", max: 2048, min: 0, step: 16, name: "repeat_last_n", value: params.value.repeat_last_n })}
-          ${FloatField({ label: "Top-P", title: "Limits the selection of the next token to a subset of tokens whose combined probability reaches a threshold value P = top-P. If set to 1, it means the entire vocabulary size is considered.", max: 1.0, min: 0.0, name: "top_p", step: 0.01, value: params.value.top_p })}
           ${FloatField({ label: "Presence Penalty", title: "A penalty that is applied if certain tokens appear repeatedly in the generated text. A higher value leads to fewer repetitions.", max: 1.0, min: 0.0, name: "presence_penalty", step: 0.01, value: params.value.presence_penalty })}
-          ${FloatField({ label: "TFS-Z", title: "Activates tail-free sampling, a method used to limit the prediction of tokens that are too frequent. The parameter z controls the strength of this limitation. A value of 1.0 means that this function is deactivated.", max: 1.0, min: 0.0, name: "tfs_z", step: 0.01, value: params.value.tfs_z })}
           ${FloatField({ label: "Frequency Penalty", title: "A penalty that is applied based on the frequency with which certain tokens occur in the training data set. A higher value results in rare tokens being favoured.", max: 1.0, min: 0.0, name: "frequency_penalty", step: 0.01, value: params.value.frequency_penalty })}
+          ${FloatField({ label: "Top-P", title: "Limits the selection of the next token to a subset of tokens whose combined probability reaches a threshold value P = top-P. If set to 1, it means the entire vocabulary size is considered.", max: 1.0, min: 0.0, name: "top_p", step: 0.01, value: params.value.top_p })}
           ${FloatField({ label: "Typical-P", title: "Activates local typical sampling, a method used to limit the prediction of tokens that are atypical in the current context. The parameter p controls the strength of this limitation. A value of 1.0 means that this function is deactivated.", max: 1.0, min: 0.0, name: "typical_p", step: 0.01, value: params.value.typical_p })}
           ${FloatField({ label: "XTC probability", title: "Sets the chance for token removal (checked once on sampler start)", max: 1.0, min: 0.0, name: "xtc_probability", step: 0.01, value: params.value.xtc_probability })}
           ${FloatField({ label: "XTC threshold", title: "Sets a minimum probability threshold for tokens to be removed", max: 0.5, min: 0.0, name: "xtc_threshold", step: 0.01, value: params.value.xtc_threshold })}
+          ${FloatField({ label: "DRY Penalty Multiplier", title: "Set the DRY repetition penalty multiplier. Default is 0.0, which disables DRY.", max: 5.0, min: 0.0, name: "dry_multiplier", step: 0.01, value: params.value.dry_multiplier })}
+          ${FloatField({ label: "DRY Base", title: "Set the DRY repetition penalty base value. Default is 1.75", max: 3.0, min: 1.0, name: "dry_base", step: 0.01, value: params.value.dry_base })}
+          ${IntField({ label: "DRY Allowed Length", title: "Tokens that extend repetition beyond this receive exponentially increasing penalty. Default is 2", max: 10, min: 1, step: 1, name: "dry_allowed_length", value: params.value.dry_allowed_length })}
+          ${IntField({ label: "DRY Penalty Last N", title: "How many tokens to scan for repetitions. Default is -1, where 0 is disabled and -1 is context size", max: 2048, min: -1, step: 16, name: "dry_penalty_last_n", value: params.value.dry_penalty_last_n })}
+          ${FloatField({ label: "TFS-Z", title: "Activates tail-free sampling, a method used to limit the prediction of tokens that are too frequent. The parameter z controls the strength of this limitation. A value of 1.0 means that this function is deactivated.", max: 1.0, min: 0.0, name: "tfs_z", step: 0.01, value: params.value.tfs_z })}
           ${IntField({ label: "Min Keep", title: "If greater than 0, samplers are forced to return N possible tokens at minimum. Default is 0", max: 10, min: 0, name: "min_keep", value: params.value.min_keep })}
         </fieldset>
 
@@ -1144,6 +1152,8 @@ document.addEventListener('DOMContentLoaded', (event) => {
     repeat_penalty: { snapValue: 1.0, snapRangeMultiplier: 4 },
     presence_penalty: { snapValue: 0.0, snapRangeMultiplier: 4 },
     frequency_penalty: { snapValue: 0.0, snapRangeMultiplier: 4 },
+    dry_multiplier: { snapValue: 0.0, snapRangeMultiplier: 4 },
+    dry_base: { snapValue: 1.75, snapRangeMultiplier: 4 },
   };
   // add an event listener for each slider
   Object.keys(snapSettings).forEach(sliderName => {

examples/server/public/index.html

@@ -304,6 +304,10 @@
       repeat_last_n: 256, // 0 = disable penalty, -1 = context size
       repeat_penalty: 1.18, // 1.0 = disabled
       penalize_nl: false,
+      dry_multiplier: 0.0, // 0.0 = disabled, 0.8 works well
+      dry_base: 1.75,     // 0.0 = disabled
+      dry_allowed_length: 2, // tokens extending repetitions beyond this receive penalty, 2 works well
+      dry_penalty_last_n: -1, // how many tokens to scan for repetitions (0 = disable penalty, -1 = context size)
       top_k: 40, // <= 0 to use vocab size
       top_p: 0.95, // 1.0 = disabled
       min_p: 0.05, // 0 = disabled
@@ -1015,6 +1019,10 @@
               ${FloatField({ label: "Typical P", max: 1.0, min: 0.0, name: "typical_p", step: 0.01, value: params.value.typical_p })}
               ${FloatField({ label: "Presence penalty", max: 1.0, min: 0.0, name: "presence_penalty", step: 0.01, value: params.value.presence_penalty })}
               ${FloatField({ label: "Frequency penalty", max: 1.0, min: 0.0, name: "frequency_penalty", step: 0.01, value: params.value.frequency_penalty })}
+              ${FloatField({ label: "DRY Penalty Multiplier", max: 5.0, min: 0.0, name: "dry_multiplier", step: 0.01, value: params.value.dry_multiplier })}
+              ${FloatField({ label: "DRY Base", max: 3.0, min: 1.0, name: "dry_base", step: 0.01, value: params.value.dry_base })}
+              ${IntField({ label: "DRY Allowed Length", max: 10, min: 2, step: 1, name: "dry_allowed_length", value: params.value.dry_allowed_length })}
+              ${IntField({ label: "DRY Penalty Last N", max: 2048, min: -1, step: 16, name: "dry_penalty_last_n", value: params.value.dry_penalty_last_n })}
               ${FloatField({ label: "XTC probability", max: 1.0, min: 0.0, name: "xtc_probability", step: 0.01, value: params.value.xtc_probability })}
               ${FloatField({ label: "XTC threshold", max: 0.5, min: 0.0, name: "xtc_threshold", step: 0.01, value: params.value.xtc_threshold })}
             </fieldset>

examples/server/server.cpp

@@ -818,6 +818,10 @@ struct server_context {
         slot.sparams.penalty_repeat     = json_value(data, "repeat_penalty",     default_sparams.penalty_repeat);
         slot.sparams.penalty_freq       = json_value(data, "frequency_penalty",  default_sparams.penalty_freq);
         slot.sparams.penalty_present    = json_value(data, "presence_penalty",   default_sparams.penalty_present);
+        slot.sparams.dry_multiplier     = json_value(data, "dry_multiplier",     default_sparams.dry_multiplier);
+        slot.sparams.dry_base           = json_value(data, "dry_base",           default_sparams.dry_base);
+        slot.sparams.dry_allowed_length = json_value(data, "dry_allowed_length", default_sparams.dry_allowed_length);
+        slot.sparams.dry_penalty_last_n = json_value(data, "dry_penalty_last_n", default_sparams.dry_penalty_last_n);
         slot.sparams.mirostat           = json_value(data, "mirostat",           default_sparams.mirostat);
         slot.sparams.mirostat_tau       = json_value(data, "mirostat_tau",       default_sparams.mirostat_tau);
         slot.sparams.mirostat_eta       = json_value(data, "mirostat_eta",       default_sparams.mirostat_eta);
@@ -830,6 +834,25 @@ struct server_context {
       //slot.params.t_max_prompt_ms     = json_value(data, "t_max_prompt_ms",    default_params.t_max_prompt_ms); // TODO: implement
         slot.params.t_max_predict_ms    = json_value(data, "t_max_predict_ms",   default_params.t_max_predict_ms);
 
+        if (slot.sparams.dry_base < 1.0f)
+        {
+           slot.sparams.dry_base = default_sparams.dry_base;
+        }
+
+        // sequence breakers for DRY
+        {
+            // Currently, this is not compatible with TextGen WebUI, Koboldcpp and SillyTavern format
+            // Ref: https://github.com/oobabooga/text-generation-webui/blob/d1af7a41ade7bd3c3a463bfa640725edb818ebaf/extensions/openai/typing.py#L39
+
+            if (data.contains("dry_sequence_breakers")) {
+                slot.sparams.dry_sequence_breakers = json_value(data, "dry_sequence_breakers", std::vector<std::string>());
+                if (slot.sparams.dry_sequence_breakers.empty()) {
+                    send_error(task, "Error: dry_sequence_breakers must be a non-empty array of strings", ERROR_TYPE_INVALID_REQUEST);
+                    return false;
+                }
+            }
+        }
+
         // process "json_schema" and "grammar"
         if (data.contains("json_schema") && !data.at("json_schema").is_null() && data.contains("grammar") && !data.at("grammar").is_null()) {
             send_error(task, "Either \"json_schema\" or \"grammar\" can be specified, but not both", ERROR_TYPE_INVALID_REQUEST);
@@ -1132,6 +1155,11 @@ struct server_context {
             {"repeat_penalty",            slot.sparams.penalty_repeat},
             {"presence_penalty",          slot.sparams.penalty_present},
             {"frequency_penalty",         slot.sparams.penalty_freq},
+            {"dry_multiplier",            slot.sparams.dry_multiplier},
+            {"dry_base",                  slot.sparams.dry_base},
+            {"dry_allowed_length",        slot.sparams.dry_allowed_length},
+            {"dry_penalty_last_n",        slot.sparams.dry_penalty_last_n},
+            {"dry_sequence_breakers",     slot.sparams.dry_sequence_breakers},
             {"mirostat",                  slot.sparams.mirostat},
             {"mirostat_tau",              slot.sparams.mirostat_tau},
             {"mirostat_eta",              slot.sparams.mirostat_eta},
@@ -1970,7 +1998,6 @@ struct server_context {
 
                                             for (size_t i = 0; i < n_match; i++) {
                                                 slot.cache_tokens[head_p + i] = slot.cache_tokens[head_c + i];
-
                                                 slot.n_past++;
                                             }
 

include/llama.h

@@ -1141,6 +1141,16 @@ extern "C" {
                                 bool   penalize_nl,     // consider newlines as a repeatable token
                                 bool   ignore_eos);     // ignore the end-of-sequence token
 
+    ///  @details DRY sampler, designed by p-e-w, as described in: https://github.com/oobabooga/text-generation-webui/pull/5677, porting Koboldcpp implementation authored by pi6am: https://github.com/LostRuins/koboldcpp/pull/982
+    LLAMA_API struct llama_sampler *    llama_sampler_init_dry(
+            const struct llama_model *  model,
+                               float    dry_multiplier,
+                               float    dry_base,
+                             int32_t    dry_allowed_length,
+                             int32_t    dry_penalty_last_n,
+                          const char ** seq_breakers,
+                              size_t    num_breakers);
+
     LLAMA_API struct llama_sampler * llama_sampler_init_logit_bias(
                              int32_t   n_vocab,
                              int32_t   n_logit_bias,

src/llama-sampling.cpp

@@ -1683,6 +1683,397 @@ struct llama_sampler * llama_sampler_init_penalties(
     };
 }
 
+// DRY
+
+struct llama_sampler_dry {
+    int32_t total_context_size;
+
+    const float   dry_multiplier;
+    const float   dry_base;
+    const int32_t dry_allowed_length;
+    const int32_t dry_penalty_last_n;
+
+    std::unordered_multimap<llama_token, std::vector<llama_token>> dry_processed_breakers;
+    std::vector<int> dry_repeat_count;
+    std::unordered_map<llama_token, int> dry_max_token_repeat;
+    ring_buffer<llama_token> last_tokens;
+};
+
+// Ported from Koboldcpp, original PR: https://github.com/LostRuins/koboldcpp/pull/982 (Original author: pi6am)
+static void get_overlapping_token_sequences(const llama_vocab & vocab, const std::string& str, std::unordered_multimap<llama_token, std::vector<llama_token>>& token_sequences, int max_tail_len = -1) {
+    for (llama_token token_id = 0; token_id < (llama_token)vocab.n_vocab; token_id++) {
+        std::string word = llama_detokenize(vocab, {token_id}, true);
+        if (word.find(str) != std::string::npos) {
+            token_sequences.emplace(token_id, std::vector<llama_token>());
+        } else {
+            size_t word_len = word.size(), str_len = str.size();
+            size_t pos = -1;
+            while ((pos = word.find(str[0], pos + 1)) != std::string::npos) {
+                bool match = true;
+                size_t i;
+                for (i = 1; i < str_len && i + pos < word_len; ++i) {
+                    if (word[pos + i] != str[i]) {
+                        match = false;
+                        break;
+                    }
+                }
+                if (match) {
+                    std::vector<llama_token> tokenization = llama_tokenize_internal(vocab, str.substr(i), false, false);
+                    if (max_tail_len >= 0 && tokenization.size() > (size_t)max_tail_len) {
+                        tokenization.resize(max_tail_len);
+                    }
+
+                    // Ensure we don't already have a duplicate matching tokenization
+                    auto its = token_sequences.equal_range(token_id);
+                    bool found = false;
+                    for (auto it = its.first; it != its.second; ++it) {
+                        if (tokenization == it->second) {
+                            found = true;
+                            break;
+                        }
+                    }
+                    if (!found) {
+                        token_sequences.emplace(token_id, tokenization);
+                    }
+                }
+            }
+        }
+    }
+}
+
+static const char * llama_sampler_dry_name(const struct llama_sampler * /*smpl*/) {
+    return "dry";
+}
+
+static void llama_sampler_dry_accept(struct llama_sampler * smpl, llama_token token) {
+    auto * ctx = (llama_sampler_dry *) smpl->ctx;
+    if (ctx->dry_multiplier == 0.0f || ctx->dry_base < 1.0f || ctx->dry_penalty_last_n == 0) {
+        return;
+    }
+
+    ctx->last_tokens.push_back(token);
+}
+
+// Ported from Koboldcpp, original PR: https://github.com/LostRuins/koboldcpp/pull/982 (Original author: pi6am)
+static void llama_sampler_dry_apply(struct llama_sampler * smpl, llama_token_data_array * cur_p) {
+    auto * ctx = (llama_sampler_dry *) smpl->ctx;
+
+    if (ctx->dry_multiplier == 0.0f || ctx->dry_base < 1.0f || ctx->dry_penalty_last_n == 0) {
+        return;
+    }
+
+    int32_t effective_dry_penalty_last_n = (ctx->dry_penalty_last_n == -1) ? ctx->total_context_size : std::max(ctx->dry_penalty_last_n, 0);
+    int last_n_repeat = std::min(std::min((int)ctx->last_tokens.size(), effective_dry_penalty_last_n), ctx->total_context_size);
+
+    if (last_n_repeat <= ctx->dry_allowed_length) {
+        return;
+    }
+
+    ctx->dry_repeat_count.assign(last_n_repeat, 0);
+    ctx->dry_max_token_repeat.clear();
+
+    // Step 1: Look for restart sequences to limit the maximum repetition length.
+    // Work backwards through the context looking for any token that begins a restart sequence.
+    //
+    // The collection `restart_sequences` is a mapping from a "head" token to all "tail"
+    // sequences that together comprise a restart sequence. This allows us to quickly check
+    // whether each token is the head of a complete sequence. Most restart sequences are actually
+    // a single token, and for these the "tail" is an empty vector.
+    //
+    // If the token is a "head", test all restart sequences that begin with this token
+    // (there will often only be one sequence for each token, but if sequences like 'aaaq1' and
+    // 'aaa1' are used as restart strings, both could start with 'aaa' when tokenized). The
+    // longest matching sequence (if any) is used to limit the maximum repetition length.
+    //
+    // Note that in the case case of a short sequence contained in a longer one, this might fail to
+    // find the smallest value for `rep_limit`. For example, if 'amniotic' and 'ni' are both used as
+    // restart sequences, 'ni' will be found first, and since it's shorter it will fail to suppress
+    // 'otic'. This is a minor issue since fully contained restart sequences are likely to be rare.
+    //
+    // This is theoretically worst-case O(N^2) for arbitrary restart sequences, which is why we
+    // have already clamped the maximum tail sequence length when generating `restart_sequences`.
+    // With clamping, this scan is O(N) in the context length.
+
+    int rep_limit = last_n_repeat;
+    for (int i = 0; i < last_n_repeat; ++i) {
+        llama_token token = ctx->last_tokens.rat(i);
+        auto its = ctx->dry_processed_breakers.equal_range(token);
+        if (its.first == ctx->dry_processed_breakers.end()) {
+            continue;
+        }
+        int longest_match = -1;
+        for (auto it = its.first; it != its.second; ++it) {
+            // Note that (*it) does not contain the head character, so seq_len will be
+            // the restart sequence length minus 1.
+            // In the common case of a single-token restart sequence, (*it) will be empty
+            // and we will trivially match.
+            int seq_len = (int)it->second.size();
+            if (seq_len > longest_match && seq_len <= (int)i) {
+                bool match = true;
+                for (int offset = 0; offset < seq_len; ++offset) {
+                    // The -1 when indexing `last_tokens` is because we already matched the head.
+                    if (it->second[offset] != ctx->last_tokens.rat(i - offset - 1)) {
+                        match = false;
+                        break;
+                    }
+                }
+                if (match) {
+                    longest_match = seq_len;
+                }
+            }
+        }
+        if (longest_match >= 0) {
+            // We found a restart sequence starting `i` tokens from the end and continuing for
+            // `longest_match` tokens.
+            rep_limit = i - longest_match;
+            break;
+        }
+    }
+    if (rep_limit < ctx->dry_allowed_length) {
+        return;
+    }
+
+    // Step 2: Iterate in reverse over the last N tokens of the context, using the "Z-algorithm" (in
+    // the reverse direction) to efficiently compute the positions and lengths of suffixes appearing
+    // elsewhere in the context. We limit the suffix length to `rep_limit` to respect restart sequences.
+    //
+    // This algorithm is not currently documented on Wikipedia, but there is a clear description here:
+    // https://ivanyu.me/blog/2014/10/15/z-algorithm/
+    //
+    // The code below is adapted from the public domain implementation by the same author here:
+    // https://github.com/ivanyu/string-algorithms/blob/master/z_algorithm.py
+    //
+    // Example:
+    // Last N tokens: a b c c b c y a b c
+    // Repeat counts: 0 0 3 1 0 2 0 0 0 0
+    //                    ^
+    //   This `3` means that the last three tokens of the context (a b c) also appear here.
+    //
+    // This step is worst case O(N) since the Z-algorithm is linear, despite the appearance of nested
+    // for/while loops. This can be seen by observing that the `lt` and `rt` bounds are set after each
+    // repeated suffix is detected (i.e. after each while loop when n > 0). These bound variables
+    // ensure that the inner while loops only examine each token in the context once as the outer
+    // for loop iterates over the context.
+
+    {
+        const int last = last_n_repeat - 1;
+        int rt = 0, lt = 0;
+
+        for (int k = 1; k < last_n_repeat; ++k) {
+            if (k > rt) {
+                // If k is outside the current Z-box, do naive computation.
+                int n = 0;
+                while (n + k < last_n_repeat && ctx->last_tokens.rat(n) == ctx->last_tokens.rat(n+k)) {
+                    ++n;
+                }
+                ctx->dry_repeat_count[last - k] = std::min(n, rep_limit);
+                if (n > 0) {
+                    lt = k;
+                    rt = k+n-1;
+                }
+            } else {
+                // If k is inside the current Z-box, consider two cases.
+
+                int p = k - lt; // Pair index.
+                int right_part_len = rt - k + 1;
+
+                if (ctx->dry_repeat_count[last - p] < right_part_len) {
+                    int n = std::min(ctx->dry_repeat_count[last - p], rep_limit);
+                    ctx->dry_repeat_count[last - k] = n;
+                } else {
+                    int i = rt + 1;
+                    while (i < last_n_repeat && ctx->last_tokens.rat(i) == ctx->last_tokens.rat(i - k)) {
+                        i += 1;
+                    }
+
+                    int n = std::min(i - k, rep_limit);
+                    ctx->dry_repeat_count[last - k] = n;
+                    lt = k;
+                    rt = i - 1;
+                }
+            }
+        }
+    }
+
+    // Step 3: Iterate over dry_repeat_count and last_tokens, examining the maximum repeat length
+    // that would be generated by emitting each new token that would extend a sequence.
+    //
+    // Following the same example as above:
+    // Last N tokens: a b c c b c y a b c
+    // Repeat counts: 0 0 3 1 0 2 0 0 0 0
+    //
+    // For each non-zero, look ahead one token. This token, if emitted, would extend the repetition.
+    // c: 3 -> 4 (from `a b c` to `a b c c`)
+    // b: 1 -> 2 (from `c` to `c b`)
+    // y: 2 -> 3 (from `b c` to `b c y`)
+
+    for (int i = 0; i < last_n_repeat - 1; ++i) {
+        int repeat_len = ctx->dry_repeat_count[i];
+        if (repeat_len >= ctx->dry_allowed_length) {
+            // This token ends a repeat, so the next token would continue one.
+            // By convention, the value of `repeat_len` only includes the tokens currently
+            // in the context, not the new token that would be added.
+            llama_token token = ctx->last_tokens.rat(last_n_repeat - 2 - i);
+            // Track the maximum sequence ending in this token.
+            const auto& it = ctx->dry_max_token_repeat.find(token);
+            if (it == ctx->dry_max_token_repeat.end() || it->second < repeat_len) {
+                ctx->dry_max_token_repeat[token] = repeat_len;
+            }
+        }
+    }
+
+    // Step 4: Apply logit penalties based on the maximum repeat length for relevant tokens.
+
+    // Prevent floating point overflow in `pow(penalty_base, exponent)` by clamping to `max_exponent`.
+    // Compute it from `penalty_base` and the approximate log of `std::numeric_limits<float>::max()`
+    const float FLOAT_MAX_LOG = 88.7228391f;
+    int max_exponent = 0;
+    if (ctx->dry_base > 1.000001f) {
+        max_exponent = FLOAT_MAX_LOG / std::log(ctx->dry_base);
+    }
+
+    for (size_t i = 0; i < cur_p->size; ++i) {
+        const auto& af_kvp = ctx->dry_max_token_repeat.find(cur_p->data[i].id);
+        if (af_kvp != ctx->dry_max_token_repeat.end()) {
+            // Check all sequence breakers starting with this token
+            auto range = ctx->dry_processed_breakers.equal_range(cur_p->data[i].id);
+            bool is_single_token_breaker = false;
+
+            for (auto it = range.first; it != range.second; ++it) {
+                if (it->second.empty()) {
+                    is_single_token_breaker = true;
+                    break;
+                }
+            }
+
+            // Apply penalty only if it's not a single-token sequence breaker
+            if (!is_single_token_breaker) {
+                int repeat_exp = af_kvp->second - ctx->dry_allowed_length;
+                if (max_exponent > 0 && repeat_exp > max_exponent) {
+                    repeat_exp = max_exponent;
+                }
+                float penalty = ctx->dry_multiplier * std::pow(ctx->dry_base, repeat_exp);
+                cur_p->data[i].logit -= penalty;
+            }
+        }
+    }
+
+    cur_p->sorted = false;
+}
+
+static void llama_sampler_dry_reset(struct llama_sampler * smpl) {
+    auto * ctx = (llama_sampler_dry *) smpl->ctx;
+    ctx->last_tokens.clear();
+    ctx->dry_repeat_count.clear();
+    ctx->dry_max_token_repeat.clear();
+}
+
+static struct llama_sampler * llama_sampler_dry_clone(const struct llama_sampler * smpl) {
+    const auto * ctx = (llama_sampler_dry *) smpl->ctx;
+
+    // nullptr is passed as vocab because it is only needed for raw sequence breaker processing, which we have already done and will be copying
+    auto * result = llama_sampler_init_dry(nullptr, ctx->dry_multiplier, ctx->dry_base, ctx->dry_allowed_length, ctx->dry_penalty_last_n, NULL, 0);
+    // Copy the state, including the processed breakers
+    {
+        auto * result_ctx = (llama_sampler_dry *) result->ctx;
+        result_ctx->dry_processed_breakers = ctx->dry_processed_breakers;
+        result_ctx->dry_repeat_count = ctx->dry_repeat_count;
+        result_ctx->dry_max_token_repeat = ctx->dry_max_token_repeat;
+        result_ctx->last_tokens = ctx->last_tokens;
+    }
+
+    return result;
+}
+
+static void llama_sampler_dry_free(struct llama_sampler * smpl) {
+    delete (llama_sampler_dry *) smpl->ctx;
+}
+
+static struct llama_sampler_i llama_sampler_dry_i = {
+    /* .name   = */ llama_sampler_dry_name,
+    /* .accept = */ llama_sampler_dry_accept,
+    /* .apply  = */ llama_sampler_dry_apply,
+    /* .reset  = */ llama_sampler_dry_reset,
+    /* .clone  = */ llama_sampler_dry_clone,
+    /* .free   = */ llama_sampler_dry_free,
+};
+
+struct llama_sampler * llama_sampler_init_dry_impl(const struct llama_vocab & vocab, int32_t context_size, float dry_multiplier, float dry_base, int32_t dry_allowed_length, int32_t dry_penalty_last_n, const char** seq_breakers, size_t num_breakers) {
+    int32_t effective_dry_penalty_last_n = (dry_penalty_last_n == -1) ? context_size : std::max(dry_penalty_last_n, 0);
+    std::unordered_multimap<llama_token, std::vector<llama_token>> processed_breakers;
+    const int MAX_CHAR_LEN = 40;
+    const int MAX_SEQ_LEN = 20;
+
+    const bool dry_enabled = (dry_multiplier != 0.0f && dry_base >= 1.0f && dry_penalty_last_n != 0);
+
+    if (dry_enabled && seq_breakers != nullptr && num_breakers > 0) {
+        // Process sequence breakers
+        for (size_t i = 0; i < num_breakers; ++i) {
+            if (seq_breakers[i] == nullptr || std::strlen(seq_breakers[i]) == 0) {
+                LLAMA_LOG_WARN("skipping null or empty DRY sequence breaker at index %zu\n", i);
+                continue;
+            }
+
+            std::string sequence_break(seq_breakers[i]);
+            if (sequence_break.empty()) {
+                LLAMA_LOG_WARN("skipping empty DRY sequence breaker\n");
+                continue;
+            }
+
+            if (sequence_break.size() > MAX_CHAR_LEN) {
+                LLAMA_LOG_WARN("truncating DRY sequence breaker to %d characters\n", MAX_CHAR_LEN);
+                sequence_break.resize(MAX_CHAR_LEN);
+            }
+
+            get_overlapping_token_sequences(vocab, sequence_break, processed_breakers, MAX_SEQ_LEN);
+        }
+    }
+
+    return new llama_sampler {
+        /* .iface = */ &llama_sampler_dry_i,
+        /* .ctx   = */ new llama_sampler_dry {
+            /* .total_context_size     = */ context_size,
+            /* .dry_multiplier         = */ dry_multiplier,
+            /* .dry_base               = */ dry_base,
+            /* .dry_allowed_length     = */ dry_allowed_length,
+            /* .dry_penalty_last_n     = */ dry_penalty_last_n,
+            /* .dry_processed_breakers = */ std::move(processed_breakers),
+            /* .dry_repeat_count       = */ dry_enabled ? std::vector<int>(effective_dry_penalty_last_n, 0) : std::vector<int>{},
+            /* .dry_max_token_repeat   = */ {},
+            /* .last_tokens            = */ dry_enabled ? ring_buffer<llama_token>(effective_dry_penalty_last_n) : ring_buffer<llama_token>(0),
+        },
+    };
+}
+
+// wrapper for test-sampling.cpp
+struct llama_sampler * llama_sampler_init_dry_testing(int32_t context_size, float dry_multiplier, float dry_base, int32_t dry_allowed_length, int32_t dry_penalty_last_n, const std::vector<std::vector<llama_token>>& seq_breakers) {
+    llama_vocab dummy_vocab;
+    auto * result = llama_sampler_init_dry_impl(dummy_vocab, context_size, dry_multiplier, dry_base, dry_allowed_length, dry_penalty_last_n, NULL, 0);
+    auto * ctx = (llama_sampler_dry *) result->ctx;
+
+    // Process the token-based sequence breakers
+    ctx->dry_processed_breakers.clear();
+    if (seq_breakers.empty()) {
+        LLAMA_LOG_WARN("empty DRY sequence breakers list in llama_sampler_init_dry_testing\n");
+    } else {
+        for (const auto& breaker : seq_breakers) {
+            if (breaker.empty()) {
+                LLAMA_LOG_WARN("skipping DRY empty sequence breaker\n");
+                continue;
+            }
+            llama_token head_token = breaker[0];
+            std::vector<llama_token> tail_tokens(breaker.begin() + 1, breaker.end());
+            ctx->dry_processed_breakers.emplace(head_token, std::move(tail_tokens));
+        }
+
+        if (ctx->dry_processed_breakers.empty()) {
+            LLAMA_LOG_WARN("no valid DRY sequence breakers processed in llama_sampler_init_dry_testing\n");
+        }
+    }
+
+    return result;
+}
+
 // logit-bias
 
 struct llama_sampler_logit_bias {

src/llama-sampling.h

@@ -28,3 +28,21 @@ struct llama_sampler * llama_sampler_init_grammar_impl(
 
 struct llama_sampler * llama_sampler_init_infill_impl(
         const struct llama_vocab & vocab);
+
+struct llama_sampler * llama_sampler_init_dry_impl(
+        const struct llama_vocab &  vocab,
+                         int32_t    context_size,
+                           float    dry_multiplier,
+                           float    dry_base,
+                         int32_t    dry_allowed_length,
+                         int32_t    dry_penalty_last_n,
+                      const char ** seq_breakers,
+                          size_t    num_breakers);
+
+struct llama_sampler * llama_sampler_init_dry_testing(
+                         int32_t   context_size,
+                           float   dry_multiplier,
+                           float   dry_base,
+                         int32_t   dry_allowed_length,
+                         int32_t   dry_penalty_last_n,
+  const std::vector<std::vector<llama_token>>& seq_breakers);

src/llama-vocab.cpp

@@ -1966,3 +1966,19 @@ int32_t llama_detokenize_impl(
 
     return total <= text_len_max ? total : -total;
 }
+
+std::string llama_detokenize(const struct llama_vocab & vocab, const std::vector<llama_token> & tokens, bool special) {
+    std::string text;
+    text.resize(std::max(text.capacity(), tokens.size()));
+    int32_t n_chars = llama_detokenize_impl(vocab, tokens.data(), (int32_t)tokens.size(), &text[0], (int32_t)text.size(), false, special);
+    if (n_chars < 0) {
+        text.resize(-n_chars);
+        n_chars = llama_detokenize_impl(vocab, tokens.data(), (int32_t)tokens.size(), &text[0], (int32_t)text.size(), false, special);
+        GGML_ASSERT(n_chars <= (int32_t)text.size());  // whitespace trimming is performed after per-token detokenization
+    }
+
+    text.resize(n_chars);
+
+    // NOTE: the original tokenizer decodes bytes after collecting the pieces.
+    return text;
+}

src/llama-vocab.h

@@ -163,3 +163,8 @@ int32_t llama_detokenize_impl(
                          int32_t   text_len_max,
                             bool   remove_special,
                             bool   unparse_special);
+
+std::string llama_detokenize(
+        const struct llama_vocab & vocab,
+  const std::vector<llama_token> & tokens,
+                            bool   special);

src/llama.cpp

@@ -21775,6 +21775,10 @@ struct llama_sampler * llama_sampler_init_infill(const struct llama_model * mode
     return llama_sampler_init_infill_impl(model->vocab);
 }
 
+struct llama_sampler * llama_sampler_init_dry(const struct llama_model * model, float dry_multiplier, float dry_base, int32_t dry_allowed_length, int32_t dry_penalty_last_n, const char** seq_breakers, size_t num_breakers) {
+    return llama_sampler_init_dry_impl(model->vocab, llama_n_ctx_train(model), dry_multiplier, dry_base, dry_allowed_length, dry_penalty_last_n, seq_breakers, num_breakers);
+}
+
 //
 // model split
 //

tests/test-sampling.cpp

@@ -10,6 +10,8 @@
 #include <string>
 #include <vector>
 
+extern struct llama_sampler * llama_sampler_init_dry_testing(int32_t context_size, float dry_multiplier, float dry_base, int32_t dry_allowed_length, int32_t dry_penalty_last_n, const std::vector<std::vector<llama_token>>& seq_breakers);
+
 static void dump(const llama_token_data_array * cur_p) {
     for (size_t i = 0; i < cur_p->size; i++) {
         printf("%d: %f (%f)\n", cur_p->data[i].id, cur_p->data[i].p, cur_p->data[i].logit);
@@ -167,6 +169,29 @@ static void test_penalties(
     tester.check();
 }
 
+static void test_dry(
+    const std::vector<float> & probs, const std::vector<llama_token> & last_tokens,
+    const std::vector<float> & expected_probs, float dry_multiplier, float dry_base,
+    int dry_allowed_length, int dry_penalty_last_n,
+    const std::vector<std::vector<llama_token>> & seq_breakers
+) {
+    GGML_ASSERT(probs.size() == expected_probs.size());
+
+    sampler_tester tester(probs, expected_probs);
+
+    auto * sampler = llama_sampler_init_dry_testing(1024, dry_multiplier, dry_base, dry_allowed_length, dry_penalty_last_n, seq_breakers);
+
+    for (size_t i = 0; i < last_tokens.size(); i++) {
+        llama_sampler_accept(sampler, last_tokens[i]);
+    }
+
+    DUMP(&tester.cur_p);
+    tester.apply(sampler);
+    tester.apply(llama_sampler_init_dist(0));
+    DUMP(&tester.cur_p);
+    tester.check();
+}
+
 static void test_sampler_queue(const size_t n_vocab, const std::string & samplers_sequence, const int top_k, const float top_p, const float min_p
 ) {
     sampler_tester tester(n_vocab);
@@ -333,6 +358,13 @@ int main(void) {
     test_penalties({0.2f, 0.2f, 0.2f, 0.2f, 0.2f}, {0, 1, 2},       {0.499966f, 0.499966f, 0.000023f, 0.000023f, 0.000023f}, 1.0f, 5.0f, 5.0f);
     test_penalties({0.2f, 0.2f, 0.2f, 0.2f, 0.2f}, {0, 1, 2, 0, 0}, {0.499977f, 0.499977f, 0.000023f, 0.000023f, 0.000000f}, 1.0f, 5.0f, 5.0f);
 
+
+    test_dry({0.25f, 0.25f, 0.25f, 0.25f}, {0, 1}, {0.25f, 0.25f, 0.25f, 0.25f}, 1.0f, 1.1f, 2, 4, {});
+    test_dry({0.25f, 0.25f, 0.25f, 0.25f}, {0, 1, 2, 0, 1}, {0.296923f, 0.296923f, 0.296923f, 0.109232f}, 1.0f, 1.1f, 2, 5, {});
+    test_dry({0.2f, 0.2f, 0.2f, 0.2f, 0.2f}, {0, 1, 3, 4, 0, 1}, {0.2f, 0.2f, 0.2f, 0.2f, 0.2f}, 1.0f, 1.1f, 2, 6, {{3}});
+    test_dry({0.2f, 0.2f, 0.2f, 0.2f, 0.2f}, {0, 1, 2, 0, 1}, {0.241818f, 0.241818f, 0.241818f, 0.241818f, 0.032727f}, 2.0f, 1.1f, 2, 5, {});
+    test_dry({0.2f, 0.2f, 0.2f, 0.2f, 0.2f}, {0, 1, 2, 3, 4, 0, 1}, {0.2f, 0.2f, 0.2f, 0.2f, 0.2f}, 1.0f, 1.1f, 4, 7, {});
+
     test_sampler_queue(10000, "k", 10000, 1.0f, 1.0f);
     test_sampler_queue(10000, "k",     1, 1.0f, 1.0f);
     test_sampler_queue(10000, "p", 10000, 1.0f, 1.0f);