What is the unit of time in MySQL's slow-query log?
I'm looking at the slow query log from a drupal-based webapp, and have lines that look like this:
# Query_time: 3257 Lock_time: 0 Rows_sent: 272 Rows_examined: 272
# Query_time: 1654 Lock_time: 0 Rows_sent: 222 Rows_examined: 222
# Query_time: 3292 Lock_time: 0 Rows_sent: 269 Rows_examined: 269
# Query_time: 1029 Lock_time: 0 Rows_sent: 172 Rows_examined: 172
# Query_time: 2126 Lock_time: 0 Rows_sent: 251 Rows_examined: 251
# Query_time: 1731 Lock_time: 0 Rows_sent: 229 Rows_examined: 229
Are th开发者_如何转开发ese times indicating that the associated queries took between 1 and 3+ seconds (slow but not terrible) to execute, or between 1,000 and 3,000+ seconds (completely unacceptable)? I understand that the long_query_time
option is specified in seconds, but do the log messages follow this same convention, or do they use milliseconds instead?
Edit: this is with MySQL version 5.0.45.
It's in seconds. The 'resolution of microseconds' means, that you can have up to microsecond precision after a decimal (although AFAIK it need a patch to actually write with such precision)
https://github.com/wvanbergen/request-log-analyzer/wiki/MySQL-slow-query-log
Only since MySQL 5.1.21 that you can specify a decimal value and has a resolution of microsecond. http://dev.mysql.com/doc/refman/5.1/en/slow-query-log.html
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