Re: Autovacuum launcher doesn't notice death of postmaster immediately

Alvaro Herrera <alvherre(at)commandprompt(dot)com> wrote:

> > No, I meant a "while (sleep 1(or 10) and counter < longtime) check for
> > exit" instead of "sleep longtime".
>
> Ah; yes, what I was proposing (or thought about proposing, not sure if I
> posted it or not) was putting a upper limit of 10 seconds in the sleep
> (bgwriter sleeps 10 seconds if configured to not do anything). Though
> 10 seconds may seem like an eternity for systems like the ones Peter was
> talking about, where there is a script trying to restart the server as
> soon as the postmaster dies.

Here is a patch for split-sleep of autovacuum_naptime.

There are some other issues in CVS HEAD; We use the calculation
{autovacuum_naptime * 1000000} in launcher_determine_sleep().
The result will be corrupted if we set autovacuum_naptime to >2147.

In another place, we use {autovacuum_naptime * 1000}, so we should
set the upper bound to INT_MAX/1000 instead of INT_MAX.
Incidentally, we've already had the same protections for
log_min_duration_statement and log_autovacuum.

I hope this patch could fix those large-autovacuum_naptime problems.

Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center