[Beowulf] Poll - Directory implementation

[Skylar Thompson]

On Fri, Oct 26, 2018 at 08:44:28PM +0000, Ryan Novosielski wrote:
> Our LDAP is very small, compared to the sorts of things some people run.
> 
> We added indexes today on uid, uidNumber, and gidNumber and the problem went away. Didn’t try it earlier as it had virtually no impact on our testing system for whatever reason, but on a different testing system and on production, it dropped “ls -al /home/“ from ~90s to ~5s. I’m not sure if all three were necessary, but I’ll look back at that later.
> 
> We’ve run SSSD from day one, so that eliminates the nscld question. We also moved CentOS 5.x to SSSD, FYI (I believe there was someone else with some old systems around). Was pretty painless, and SSSD eliminates a lot of problems that exist with the older stuff (including some really boneheaded very large LDAP queries that were happening routinely with the older nss-ldap software if I’m remembering its name correctly).

Have you experimented with client-side caching services like nscd? nscd has
its quirks (in particular, it does very poorly with caching spurious negative
results from transient network failures), but it also is a big performance
improvement since you don't even have to hit the network or the directory
services.

-- 
Skylar