Lonni J Friedman <netllama@gmail.com> writes:
> After banging my head on the wall for a long time, I happened to
> notice that khugepaged was consuming 100% CPU every time autovacuum
> was running. I did:
> echo "madvise" > /sys/kernel/mm/transparent_hugepage/defrag
> and immediately the entire problem went away.
Fascinating.
> So this looks like a nasty Fedora16 kernel bug to me, or maybe
> postgresql & Fedora16's default kernel settings are just not
> compatible?
I agree, kernel bug. What kernel version are you using exactly?
> Is anyone else using Fedora16 & PostgreSQL-9.1 ?
I use an F16 box daily, but can't claim to have done major performance
testing with it. Can you put together a summary of your nondefault
Postgres settings? I wonder whether it only kicks in for a certain
size of shared memory for instance.
regards, tom lane
