diff --git a/gpttype_adapter.cpp b/gpttype_adapter.cpp
index 1a862cf77..c0bd6bee4 100644
--- a/gpttype_adapter.cpp
+++ b/gpttype_adapter.cpp
@@ -596,8 +596,8 @@ void PurgeMissingTokens(llama_context * ctx, std::vector<int> &current_context_t
     //if passed, save beginning of LCQ from old ctx as p1
     //remove all tokens from old ctx between p0 and p1, updating both arrays and kv, then continue as normal
 
-    const int ShortfallThreshold = 200; //dont trigger shifting if the distance between trimstart and currhead < this
-    const int SlackAllowance = 50; //in case the end text is slightly modified, be forgiving
+    const int ShortfallThreshold = 200 + (nctx/40); //dont trigger shifting if the distance between trimstart and currhead < this
+    const int SlackAllowance = 50 + (nctx/80); //in case the end text is slightly modified, be forgiving
 
     int trimstart = 0;
     int new_tokens_len = new_context_tokens.size();