Re: OpenLDAP system architecture?

[Brad Knowles <b.knowles@its.utexas.edu>]

On Thu, 2008-01-24 at 18:55 -0500, Joseph Dickson wrote:

> Since the original poster mentions high end hardware, I'm going to 
> assume Solaris is the platform.. If so, he'll likely be choosing between 
> either UFS or ZFS..

I believe that the current machines are Solaris, but there has
previously been discussion of throwing those boxes out the door and
going with Linux instead.  One factor would be the synchronous versus
asynchronous syslog factor, although an alternative would be to install
a syslog replacement on Solaris that can handle asynchronous mode as
well as synchronous.  I'm not sure what the other factors are.

> In the case of UFS, logging (meta-data only journaling) is on by default 
> in Solaris 10.  Performance impact here should be negligible, even in a 
> high-write scenario.
> 
> In the case of ZFS, logging is mandatory and cannot be disabled or 
> circumvented.  This is due to the nature of the filesystem -- it employs 
> a copy-on-write strategy for ALL blocks, all of the time.  This is the 
> equivelant to full-block journaling, and I'm not sure how much it would 
> impact the performance of a high-write scenario.  I haven't used ZFS 
> much in the real world yet.

I don't know what kind of filesystem is currently being used, but I'm
guessing it's probably UFS, although it could also be mounting the data
via NFS.  I'd seriously consider ZFS, if I thought there was a good
chance that there might be a performance or reliability win.

Thanks!

-- 
Brad Knowles <b.knowles@its.utexas.edu>
Sr. System Administrator, UT Austin ITS-Unix
COM 24 | 5-9342