Increase minimum debug.log size to 10MB after shrink.

1 files changed, 6 insertions, 2 deletions

diff --git a/src/util.cpp b/src/util.cpp
index 08ee6b8b87..ba157625d8 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -723,13 +723,17 @@ void AllocateFileRange(FILE *file, unsigned int offset, unsigned int length) {
 
 void ShrinkDebugFile()
 {
+    // Amount of debug.log to save at end when shrinking (must fit in memory)
+    constexpr size_t RECENT_DEBUG_HISTORY_SIZE = 10 * 1000000;
     // Scroll debug.log if it's getting too big
     boost::filesystem::path pathLog = GetDataDir() / "debug.log";
     FILE* file = fopen(pathLog.string().c_str(), "r");
-    if (file && boost::filesystem::file_size(pathLog) > 10 * 1000000)
+    // If debug.log file is more than 10% bigger the RECENT_DEBUG_HISTORY_SIZE
+    // trim it down by saving only the last RECENT_DEBUG_HISTORY_SIZE bytes
+    if (file && boost::filesystem::file_size(pathLog) > 11 * (RECENT_DEBUG_HISTORY_SIZE / 10))
     {
         // Restart the file with some of the end
-        std::vector <char> vch(200000,0);
+        std::vector<char> vch(RECENT_DEBUG_HISTORY_SIZE, 0);
         fseek(file, -((long)vch.size()), SEEK_END);
         int nBytes = fread(vch.data(), 1, vch.size(), file);
         fclose(file);