feat(monitoring): add GC stats to CS charts LS-344

[GigaCronos]

This commit introduces a chunkserver-side feature to display Garbage Collector(GC) deletions per minute in the CGI chart of the chunkserver(CS).

When a chunk is moved to the .trash.bin directory(if Garbage Collector is ENABLED) the chunk is marked as deleted and added to chunks deleted stats in the chunkserver. Tracking when the chunk is actually deleted(purged) by the GC is needed for better testing of this feature and more precise information.

[gemini-code-assist]

Summary of Changes

Hello @GigaCronos, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the chunkserver monitoring capabilities by adding a new chart that visualizes the rate of chunk deletions performed by the Garbage Collector. This provides better insight into the efficiency and activity of the GC process on individual chunkservers, aiding in performance analysis and debugging.

Highlights

• New Monitoring Chart: Introduced a new chart to display Garbage Collector (GC) purge operations per minute on chunkserver CGI monitoring pages.
• GC Purge Statistics Tracking: Implemented a mechanism within the HddStats module to track and expose the number of chunk deletions performed by the GC.
• Integration with Charting System: Integrated the new GC purge statistics into the existing chunkserver charting data refresh logic and CGI interface definitions.

Changelog

• src/cgi/sfs.cgi.in
  • Added a new entry for 'gcpurge' to the list of chart definitions, associating it with ID 31 and a description 'number of chunk purged by GC per minute'.
• src/chunkserver/chartsdata.cc
  • Defined CHARTS_GC_PURGE as 31.
  • Incremented CHARTS_NUMBER from 31 to 32 to accommodate the new chart.
  • Added a new chart definition for 'gcpurge' with CHARTS_MODE_ADD.
  • Declared a new uint32_t variable opsGCPurge.
  • Modified the call to HddStats::operationStats to pass &opsGCPurge.
  • Assigned the value of opsGCPurge to data[CHARTS_GC_PURGE].
• src/chunkserver/chunkserver-common/chunk_trash_manager_impl.cc
  • Included hdd_stats.h.
  • Incremented HddStats::gStatsOperationsGCPurge each time a file is successfully removed from trash by the GC.
• src/chunkserver/chunkserver-common/hdd_stats.cc
  • Included <cstdint>.
  • Modified the operationStats function signature to accept an additional uint32_t *opsGCPurge parameter.
  • Exchanged the value of gStatsOperationsGCPurge and assigned it to *opsGCPurge.
• src/chunkserver/chunkserver-common/hdd_stats.h
  • Declared inline std::atomic<uint32_t> gStatsOperationsGCPurge(0);.
  • Updated the operationStats function prototype to include the uint32_t *opsGCPurge parameter.

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[gemini-code-assist]

Code Review

This pull request adds a new chart to the chunkserver monitoring CGI to display the number of chunks purged by the Garbage Collector per minute. The changes are well-contained and correctly implement the new feature by adding a new statistic, tracking it in HddStats, and exposing it through the charting infrastructure. The implementation looks solid. I have a few minor suggestions to improve code formatting for better readability.

[GigaCronos]

/gemini review

[gemini-code-assist]

Code Review

This pull request successfully adds a new chart for monitoring Garbage Collector purges on the chunkserver. The changes are implemented consistently across the C++ backend and the Python CGI script. The core logic looks good.

I've provided a few review comments. One addresses header dependency management. The others suggest reverting some code formatting changes that reduce readability and consistency with the existing codebase.

[ralcolea]

Great job @GigaCronos! 👍