missing objects -- prevention

Hi all,

I find a lot of info on how to recover from and/or repair a repo that has missing (or corrupted) objects.

What I need is info on common reasons (other than disk errors -- we've checked for those) for such errors to occur, any preventive measures we can take, and so on. For example, can *any* type of network error or race condition cause this? (Say, can one push writes an object, then fails an update check, and a later push succeeds and races against a gc that removes the unreachable object?) Or... the repo is pretty large -- about 6-7 GB, so could size cause a race that would not show up on a smaller repo?

Anything else I can watch out for or caution the team about?

The symptom is usually a disk space crunch caused by tmp_pack_* files left around by auto-gc. Presumably the missing objects failed the gc and so it left the files around, and they eventually accumulate enough to cause disk full errors. (If a gc ever succeeded, I suspect these files would go away, but that requires manual intervention).

I would appreciate any thoughts...  Thanks!