server : add n_discard parameter (ggerganov#6300)

hodlen · Apr 3, 2024 · f6df2ba · f6df2ba
1 parent f987b5c
commit f6df2ba
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/examples/server/server.cpp b/examples/server/server.cpp
@@ -99,6 +99,7 @@ struct slot_params {
 
  uint32_t seed = -1; // RNG seed
  int32_t n_keep = 0; // number of tokens to keep from initial prompt
+ int32_t n_discard = 0; // number of tokens after n_keep that may be discarded when shifting context, 0 defaults to half
  int32_t n_predict = -1; // new tokens to predict
 
  std::vector<std::string> antiprompt;
@@ -846,6 +847,7 @@ struct server_context {
  slot.sparams.mirostat_eta = json_value(data, "mirostat_eta", default_sparams.mirostat_eta);
  slot.sparams.penalize_nl = json_value(data, "penalize_nl", default_sparams.penalize_nl);
  slot.params.n_keep = json_value(data, "n_keep", slot.params.n_keep);
+ slot.params.n_discard = json_value(data, "n_discard", default_params.n_discard);
  slot.params.seed = json_value(data, "seed", default_params.seed);
  slot.sparams.n_probs = json_value(data, "n_probs", default_sparams.n_probs);
  slot.sparams.min_keep = json_value(data, "min_keep", default_sparams.min_keep);
@@ -1253,6 +1255,7 @@ struct server_context {
  {"stop", slot.params.antiprompt},
  {"n_predict", slot.params.n_predict}, // TODO: fix duplicate key n_predict
  {"n_keep", slot.params.n_keep},
+ {"n_discard", slot.params.n_discard},
  {"ignore_eos", ignore_eos},
  {"stream", slot.params.stream},
  {"logit_bias", slot.sparams.logit_bias},
@@ -1696,7 +1699,7 @@ struct server_context {
  // Shift context
  const int n_keep = slot.params.n_keep + add_bos_token;
  const int n_left = (int) system_tokens.size() + slot.n_past - n_keep;
- const int n_discard = n_left / 2;
+ const int n_discard = slot.params.n_discard ? slot.params.n_discard : (n_left / 2);
 
  LOG_INFO("slot context shift", {
  {"id_slot", slot.id},