[Date Prev][Date Next] [Chronological] [Thread] [Top]

RE: [ldap] Implementation Suggestions

Quanah Gibson-Mount wrote:
> --On Friday, January 20, 2006 8:14 PM +0000 "Spicer, Kevin"
> <KevinS@bmrb.co.uk> wrote:
>> You have enough memory for 1.25 Gb of bdb cache?  You don't post your
>> machine spec so its difficult to say if that is sane, but make sure
>> its not using lots of swap.  I note that your bdb logs are on the
>> same disk as your swap (and your syslogs presumably), so if you are
>> swapping (or anything is logging heavily) that will have an impact
>> on bdb writes. 
> Hm, interesting...
> My database is on the same drive as my swap, in my case.  All of my
> logs (bdb, syslog) are together on a separate drive.  Other than the
> fact that logging always slows things down on Solaris 8/9 (the "-"
> option in Linux largely negates this for that platform), I've not
> seen this be too negative an impact.  My Linux systems have
> everything on a single mirrored disk at the moment (and are screaming
> fast comparatively). 

I should point out that I was merely hypothesising about possible causes
for a bunch of writes to get bogged down, that a memory shortage could
result in excessive swapping which would affect performance -
particularly on the drive containing the swap.  Of course excessive
swapping would also harm performance in all sorts of other ways.  In any
case splitting the bdb logs onto another disk is not the best answer -
increasing physical memory or reducing memory usage is, but no-one needs
me to tell them that ;)


BMRB wins two BMRA awards - http://www.bmrb.co.uk
This message (and any attachment) is intended only for the 
recipient and may contain confidential and/or privileged 
material.  If you have received this in error, please contact the 
sender and delete this message immediately.  Disclosure, copying 
or other action taken in respect of this email or in 
reliance on it is prohibited.  BMRB Limited accepts no liability 
in relation to any personal emails, or content of any email which 
does not directly relate to our business.