Why Use accesslog overlay?

[Pete Giesin <pgiesin@hubcitymedia.com>]

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?

Thanks,
Pete