sharpetronics/PostgreSQL
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-05-30 00:02:11 -04:00
Code Issues Projects Releases Wiki Activity

Fix base backup rate limiting in presence of slow i/o

Browse Source 
When source i/o on disk was too slow compared to the rate limiting
specified, the system could end up with a negative value for sleep that
it never got out of, which caused rate limiting to effectively be
turned off.

Discussion: https://postgr.es/m/CABUevEy_-e0YvL4ayoX8bH_Ja9w%2BBHoP6jUgdxZuG2nEj3uAfQ%40mail.gmail.com

Analysis by me, patch by Antonin Houska
This commit is contained in:
Magnus Hagander 2016-12-19 10:11:04 +01:00
parent cc07e06b1e
commit 10238fad03
1 changed files with 7 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
src/backend/replication/basebackup.c
View File

@ -1370,26 +1370,16 @@ throttle(size_t increment)
if (wait_result & WL_LATCH_SET)
CHECK_FOR_INTERRUPTS();
}
else
{
/*
* The actual transfer rate is below the limit. A negative value
* would distort the adjustment of throttled_last.
*/
wait_result = 0;
sleep = 0;
}
/*
* Only a whole multiple of throttling_sample was processed. The rest will
* be done during the next call of this function.
* As we work with integers, only whole multiple of throttling_sample was
* processed. The rest will be done during the next call of this function.
*/
throttling_counter %= throttling_sample;
/* Once the (possible) sleep has ended, new period starts. */
if (wait_result & WL_TIMEOUT)
throttled_last += elapsed + sleep;
else if (sleep > 0)
/* Sleep was necessary but might have been interrupted. */
throttled_last = GetCurrentIntegerTimestamp();
/*
* Time interval for the remaining amount and possible next increments
* starts now.
*/
throttled_last = GetCurrentIntegerTimestamp();
}