Ryan, > On Jan 12, 2020, at 3:03 PM, Ryan C. Underwood <nemesis-li...@icequake.net> > wrote: > > I have a reproducible scenario where the cache manager populates the > cache with a zero-byte file entry. This happens when populating the > cache with a large directory tree of a web application. The client > and fileserver communicate over the internet, so sporadic packet loss > may be implicated.
If you can supply a zipped directory tree (or an AFS volume dump) that reproduces the problem, others can try to reproduce this under a debugger. > > The only resolution I have found so far is to stop the AFS client, > delete the cache and restart it and attempt cache population again. It's worth trying 'fs flushall' as a workaround if you haven't tried that yet. If it works, it will save you a client restart. And if it works, you could try narrowing things down a bit with 'fs flushvol' or 'fs flush'. > Without going into too much detail immediately, is there a recommended > way to go about debugging this sort of issue? Some type of trace might be helpful, certainly. What's your host operating system? Presuming a Linux distro, systemtap may be helpful. There's also the OpenAFS built-in fstrace, which is sometimes helpful, sometimes not so much. But I think attempting to duplicate the problem elsewhere will get answers more quickly. I could supply some trace suggestions if no one else can reproduce this problem. > This particular issue > has been observed with 1.6.x clients and with the most recent 1.8 > clients as well. Which 1.8.x clients have you tried? There are some fixes in 1.8.3, and possibly 1.8.4, that may be relevant to this problem. I'm thinking specifically of 'afs: Do not ignore errors in afs_CacheFetchProc' in 1.8.3. I also see a few candidates that have been merged to master but haven't yet been ported to 1.8.x: 13436 afs: Check dcache size when checking DVs 13435 afs: Introduce afs_IsDCacheFresh Regards, -- Mark Vitale Sine Nomine Associates 20 Years of Customer Success _______________________________________________ OpenAFS-info mailing list OpenAFS-info@openafs.org https://lists.openafs.org/mailman/listinfo/openafs-info
