Merge pull request #202 from TheLindaProjectInc/shrinkVMLog

Shrink VM Log on startup

README.md

@@ -32,7 +32,7 @@ These are some resources that might be helpful in understanding Metrix.
 
 Basic usage resources:
 
-* [User guide Wiki](https://wiki.metrixcoin.com)
+* [User guide Wiki](https://docs.metrixcoin.com)
 * [Block explorer](https://explorer.metrixcoin.com)
 * [Testnet Block explorer](https://testnet-explorer.metrixcoin.com)
 

configure.ac

@@ -3,7 +3,7 @@ AC_PREREQ([2.60])
 define(_CLIENT_VERSION_MAJOR, 4)
 define(_CLIENT_VERSION_MINOR, 2)
 define(_CLIENT_VERSION_REVISION, 0)
-define(_CLIENT_VERSION_BUILD, 0)
+define(_CLIENT_VERSION_BUILD, 1)
 define(_CLIENT_VERSION_RC, 0)
 define(_CLIENT_VERSION_IS_RELEASE, true)
 define(_COPYRIGHT_YEAR, 2023)

doc/release-notes/release-notes-4.2.0.1.md

@@ -0,0 +1,16 @@
+# Metrix Core v4.2.0.1
+
+## Bugfix Update
+
+This update addresses an issue where the vm.log file can grow to huge sizes if left unattended. The daemon will now trim this file on startup to prevent this excessive bloat.
+
+## Bug Reporting
+
+Please report bugs using the issue tracker at github: https://github.com/thelindaproject/metrix/issues
+
+## How to Upgrade
+Shut down Metrix, wait until it has completely shut down (which might take a few minutes
+for older versions), then just copy over the appropriate metrixd file.
+
+## What's Changed
+- Added shrink for the vm.log on daemon startup.

src/init.cpp

@@ -1346,6 +1346,7 @@ bool AppInitMain(NodeContext& node)
  // Do this first since it both loads a bunch of debug.log into memory,
  // and because this needs to happen before any other debug.log printing
  LogInstance().ShrinkDebugFile();
+ LogInstance().ShrinkVMLogFile();
  }
  }
  if (!LogInstance().StartLogging()) {

src/logging.cpp

@@ -134,6 +134,11 @@ bool BCLog::Logger::WillLogCategory(BCLog::LogFlags category) const
  return (m_categories.load(std::memory_order_relaxed) & category) != 0;
 }
 
+bool BCLog::Logger::DefaultShrinkVMLogFile() const
+{
+ return m_categories == BCLog::NONE;
+}
+
 bool BCLog::Logger::DefaultShrinkDebugFile() const
 {
  return m_categories == BCLog::NONE;
@@ -323,6 +328,47 @@ void BCLog::Logger::LogPrintStr(const std::string& str, bool useVMLog)
  }
 }
 
+void BCLog::Logger::ShrinkVMLogFile()
+{
+ // Amount of vm.log to save at end when shrinking (must fit in memory)
+ constexpr size_t RECENT_DEBUG_HISTORY_SIZE = 10 * 1000000;
+
+ assert(!m_file_pathVM.empty());
+
+ // Scroll vm.log if it's getting too big
+ FILE* file = fsbridge::fopen(m_file_pathVM, "r");
+
+ // Special files (e.g. device nodes) may not have a size.
+ size_t log_size = 0;
+ try {
+ log_size = fs::file_size(m_file_pathVM);
+ } catch (const fs::filesystem_error&) {}
+
+ // If vm.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 && log_size > 11 * (RECENT_DEBUG_HISTORY_SIZE / 10))
+ {
+ // Restart the file with some of the end
+ std::vector<char> vch(RECENT_DEBUG_HISTORY_SIZE, 0);
+ if (fseek(file, -((long)vch.size()), SEEK_END)) {
+ LogPrintf("Failed to shrink VM log file: fseek(...) failed\n");
+ fclose(file);
+ return;
+ }
+ int nBytes = fread(vch.data(), 1, vch.size(), file);
+ fclose(file);
+
+ file = fsbridge::fopen(m_file_pathVM, "w");
+ if (file)
+ {
+ fwrite(vch.data(), 1, nBytes, file);
+ fclose(file);
+ }
+ }
+ else if (file != nullptr)
+ fclose(file);
+}
+
 void BCLog::Logger::ShrinkDebugFile()
 {
  // Amount of debug.log to save at end when shrinking (must fit in memory)

src/logging.h

@@ -123,6 +123,7 @@ namespace BCLog {
  void DisconnectTestLogger();
 
  void ShrinkDebugFile();
+ void ShrinkVMLogFile();
 
  uint32_t GetCategoryMask() const { return m_categories.load(); }
 
@@ -134,6 +135,7 @@ namespace BCLog {
  bool WillLogCategory(LogFlags category) const;
 
  bool DefaultShrinkDebugFile() const;
+ bool DefaultShrinkVMLogFile() const;
  };
 
 } // namespace BCLog