Re: [gentoo-hardened] mySQL twice as slow on hardened (grsec) sources?

[Christian Parpart]

On Thursday 19 July 2007 10:37:56 Brad Plant wrote:
> Hi Christian,
>
> Perhaps try booting a standard kernel using the hardened profile and see
> how long that takes. If it takes closer to 12 hours, then the slowdown is
> caused by the kernel. If it still takes about 24 hours, then it is caused
> by the hardened profile.

i'm going to check this on weekend, yup. thx so far.

> On another note, have you trying tweaking the options in /etc/mysql/my.cnf?
> Increasing some of the buffer sizes might improve things, although this
> would perhaps be more applicable if mysqld was IO bound instead of CPU
> bound as in your case. Might be still worth googling for mysqld
> optimisations anyway.

i assumed to have checked the my.cnf, however we guess *one* reason might be 
that this host *maybe* used innodb as the default table engine which is now 
myisam. and myisam is known to be much slower - unfortunately.

thanks,
Christian Parpart.

> On Thu, 19 Jul 2007 10:14:06 +0200
>
> Christian Parpart <trapni@g.o> wrote:
> > Hi all,
> >
> > I just migrated a standard gentoo/linux to a hardened profile
> > including hardened-sources with grsecurity enabled and PaX-disabled.
> >
> > Well, it is basically used as a mySQL server, however, we do a biig
> > sql db import once a week to operate on it. the import took about 12
> > hours. but now, using the hardened sourced and the hardened profile
> > built system it really taked about 24+ hours.
> >
> > this really confuses me. can it be because of the extra validations
> > the kernel-/userspace has to perform?
> >
> > mysqld still ran at 100%, before the hardened migration and after.
> >
> > because *if* it is really the hardened enabled stuff that lowers the
> > performance that much, than we need to revert to non-hardened - and I
> > don't like that idea yet :)
> >
> > Any hints on this topic are really welcome,
> > Thanks in advance,
> > Christian Parpart.