Hi Maarten
On Tue, 18 Oct 2005, Maarten Litmaath, CERN wrote:
> Say we propose that for the next LCG-2 release sites should
> configure 1000 pool acounts per VO: would any of you object,
> and why? Better ideas are welcome too.
Objections off the top of my head would be (we run 232 CPUs in our LCG
setup now, with another 200 to be added in the near future)
- We support local users on the same systems. /etc/passwd files become a
little painful to manage if there are 100's to 1000's of user accounts.
- Each account takes a little bite out of /home and /scr areas, especially
if files get left behind after job crashes or other mishaps. Yes, cron
jobs can clean these areas, but anything x 1,000 gets big pretty fast.
Filling a /home area (we only assigned 200MB for this) would affect all
future submissions.
- Condor accounting counts each VO account as a separate user. Scanning
web pages etc., to get a "gestalt" impression of system performance means
there is lots of visual clutter if each job is a separate VO account. It
also becomes a lot trickier to distinguish between a heavy user, or a
large number of users.
- If one wanted to perform mass system operations on say a heavy user
submitting a large number of jobs then a useful trick is to specify the VO
user which needs jobs held, deleted or whatever. This would be rather
painful if one had to track down which N VO accounts have been assigned to
this particular submission.
- Same issues apply to data that might be stored on SE's if each file
belongs to a different user account - much harder to perform mass
monitoring or system operations.
Hope this helps....I suspect others will scream louder ;-).
Leslie
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