Extreme load with local password db lookups

[Dennis Berger]

A common way to debug is to isolate the affected systemcalls, by using 
tools like ktrace or strace.
Strace can also record a timestamp, you can see how long it takes to 
complete a specific systemcall

# strace -r -f <serverproc>
Do a single login and then examine the results.

happy debugging.

regards,
Dennis

Jeremy Chadwick schrieb:
> On Thu, Dec 06, 2007 at 06:22:07PM +0700, Eugene Grosbein wrote:
>   
>> On Thu, Dec 06, 2007 at 11:37:50AM +0100, Patrick van Iersel wrote:
>>
>>     
>>> Here's the situation. We have an web/ftp server with around 74000 users
>>> defined in the local unix password database. On 4.9-stable which it is
>>> running now, there is no noticable load when lookups are done (logins via
>>> ftp, ~user lookups from apache etc.). We want to migrate this system to
>>> 6-stable.
>>> However on 6-STABLE (FreeBSD 6.3-PRERELEASE #0: Wed Dec  5 13:35:05 CET
>>> 2007) these same lookups cause very high load and things slow down to a
>>> crawl.
>>>
>>> Does anybody have an idea what causes this behavior?
>>>
>>> Thanx in advance for any insights.
>>>       
>> Take a look to your /etc/nsswitch.conf. If you do not use NIS,
>> try to change lines for 'group' and 'passwd' to look like this:
>>
>> group: files
>> passwd: files
>>     
>
> The default value is "compat" on both RELENG_6 and RELENG_7.  I don't
> think switching to "files" will fix his problem (I'll be very surprised
> if it does).
>
>