Jim: It's been a while, but I started looking into this again a couple days ago. The file deletion being slow is something we've decided to push back after 1.0, since it doesn't really seem like a serious issue. The other two problems we wanted to solve, though, and I think we've succeeded. I was unable to reproduce your problem with ls on recent branches, and just pushed a fix for the slow dd-truncate-dd to both the master and stable branches. When you get the chance, please test one of those out and let me know if you still see issues like this. Thanks! -Greg On Tue, Dec 7, 2010 at 7:14 AM, Jim Schutt <jaschut@xxxxxxxxxx> wrote: > > Hi Sage, > > On Sat, 2010-12-04 at 21:59 -0700, Sage Weil wrote: >> Hi Jim, >> >> I think there are at least two different things going on here. >> >> On Fri, 3 Dec 2010, Jim Schutt wrote: >> > On Fri, 2010-12-03 at 15:36 -0700, Gregory Farnum wrote: >> > > How are you generating these files? It sounds like maybe you're >> doing >> > > them concurrently on a bunch of clients? >> > >> > When I created the files initially, I did it via one >> > dd per client over 64 clients, all at the same time. >> > >> > When I used echo to truncate them to zero length, I >> > did all files from one client. Also, when I removed >> > the files, I did them all from a single client. >> >> The MDS doesn't release objects on deleted files until all references >> to >> the file go away (i.e. everyone closes the file handle). The client >> make >> a point of releasing it's capability on inodes it unlinks, but since >> the >> unlink happened on a different node, the writer doesn't realize it's >> unlinked and doesn't bother to release its capability (until it gets >> pushed out of the inode cache due to normal cache pressure). I >> suspect >> this will need some additional messaging to get the client to drop it >> sooner. >> >> http://tracker.newdream.net/issues/630 >> >> That fix won't make it into 0.24, sorry! Probably 0.24.1. >> > > Thanks for tracking this! Whatever priority you assign > works great for me. > > -- Jim > > > > > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
