Turning off the accesslog completely did increase writes but only to ~200 per sec. That is still not an acceptable number. So I need to figure out how to tweak OpenLDAP to increase write performance for both my primary backend and the accesslog backend.
Here is my configuration for the accesslog database. These are basically straight out of the box. I am not sure how best to tweak these to increase writes. My current configuration has both the db and log files for both the log and primary databases on the same disk. I realize that split these across multiple disks would help with the write performance. Any other suggestions on how to imrpove write performance would be greatly appreciated. Thanks, Pete slapd.conf ------------------------- #Access Log database database hdb suffix "cn=log" rootdn "cn=Manager,cn=log" rootpw secret directory /opt/symas/var/openldap-data/access # Indices to maintain index reqStart eq index objectClass eq DB_CONFIG ------------------------ # one 0.25 GB cache set_cachesize 0 268435456 1 # Data Directory #set_data_dir db # Transaction Log settings set_lg_regionmax 262144 set_lg_bsize 2097152 set_lg_dir /opt/symas/var/openldap-logs/access On Fri, Mar 20, 2009 at 3:56 PM, Russell Jackson <[email protected]> wrote: > Pete Giesin wrote: > > I am working on setting up OpenLDAP for a web project. I had originally > planned on > > using the accesslog overlay to track all access to the LDAP. I have > discovered that the > > use of this overlay has a tremendous impact on performance. > > > > I started out by auditing all operations. With this configuration I was > getting 40-50 > > reads/sec max. I then decided that I only needed to audit writes. Making > this change > > sent the reads through the roof, but the writes were still only averaging > 16-20 per > > second. I am in the process of retesting the writes with no accesslog. My > assumption is > > that the writes per second will jump dramtically. > > > > So I have to question what is the purpose of the accesslog overlay? Is it > really needed > > and if so is there are way to increase its performance. I have to admit > that I have not > > paid attention to the settings for the accesslog backend. Do I need to > tweak these > > settings just like I did for my primary backend? If so what are the > optimal settings > > for a write intensive database? > > > > I'm sure there will be disagreement over what I'm about to say, but if your > application is > write intensive, OpenLDAP is probably the wrong tool for the job. That > said, if you tune > the bdb backend for the access log correctly, you should be able to get > many order of > magnitudes better performance out of it. > > -- > Russell A. Jackson <[email protected]> > Network Analyst > California State University, Bakersfield > > What the scientists have in their briefcases is terrifying. > -- Nikita Khruschev > >
