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Re: What expect to log at info level?

Nick Urbanik wrote:
Dear Aaron,

On 19/09/11 19:40 -0400, Aaron Richton wrote:
On Tue, 20 Sep 2011, Nick Urbanik wrote:

What I have said is that with *only* loglevel stats, in our production
servers, the write load is excessive, sometimes filling up the hard

They can be large. We rotate (including compression) nightly.
Fortunately they do compress very well...

...but compressing 25 GB files in itself takes away resources from
answering the large number of LDAP queries.

disk in four days.  The disk I/O from the logging of stats at debug
priority is excessive.  Of course, only OpenLDAP was logging at
debug level.

At a minimum, make sure that your syslog daemon isn't flushing on
each write. (With some daemons, -/file/name disables this.)

Naturally, we do that.

Actually, we do remote syslog (@loghost) so the UDP is
send-and-forget from our live servers, so there's no disk I/O at all.

Each member of our cluster of four LDAP slaves in Sydney generates
about 25 GB per day with loglevel set to 'stats'.  The cluster of
three in Melbourne are less busy, but still fairly prolific.  Imagine
sending 1 additional terabyte of data to our syslog servers every ten
days, and you need money to pay for the additional infrastructure.

(Note that none of the above is particular to OpenLDAP; we do this
with most of our services.)

Agreed; basic system administration.

Perhaps our production OpenLDAP servers work harder than the
servers everyone else here on the list manages?  It's possible: we
are a large ISP, and we provision all our services with OpenLDAP.

There are some pretty large installations watching the list...

But clearly most are smaller than our installation.

I've raised bug http://www.openldap.org/its/index.cgi/Incoming?id=7046

Obviously since OpenLDAP's behavior here is "by design" it is not a bug. Just a note - there have been at least two attempts to overhaul the Debug/Syslog support in recent years. Neither made visible progress. At this point the infrastructure exists to log individual messages at distinct priority levels, but nobody has been interested in taking the time to sift through all of the existing Debug messages and assign them specific priorities. If you would like to see your bug report make any progress, most likely you are going to need to come up with the person with that time and motivation.

  -- Howard Chu
  CTO, Symas Corp.           http://www.symas.com
  Director, Highland Sun     http://highlandsun.com/hyc/
  Chief Architect, OpenLDAP  http://www.openldap.org/project/