major/MySQLTuner-perl

Recommendation on table_open_cache_instances

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#480 opened on Feb 4, 2020

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 (1 comment) (2 reactions) (1 assignee)Perl (1,293 forks)batch import
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Description

table_open_cache could be a source of contention as default value is 1 in mysql version prior to 7.

The recommended value is 0.5 per CPU to split work load across CPU and reduce locking issue on the table cache partition. Using a big value doesn't reduce performance. Mysql 7 have a default value at 16.

Contributor guide

Research direction
Review MySQL documentation on table open cache instances and locate the relevant section in the Perl script where similar cache recommendations are made. Then add a check for table open cache instances value and suggest an appropriate setting based on CPU count.
Tech stack
perlsql
Domain
database
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
PerlMySQL
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70