| To: | xfs@xxxxxxxxxxx |
|---|---|
| Subject: | Request for information on bloated writes using Swift |
| From: | Dilip Simha <nmdilipsimha@xxxxxxxxx> |
| Date: | Tue, 2 Feb 2016 14:32:27 -0800 |
| Delivered-to: | xfs@xxxxxxxxxxx |
| Dkim-signature: | v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:from:date:message-id:subject:to:content-type; bh=MHBbkKMjPAmzv2um/Oru1TixgPdXer6E3829nBEpKeY=; b=gSx4MtWI1hKwl/N15pjuQR19XuPR848Zle5MeWogU0yZo7J9/j/bikoO6i33VTdzKF smYK/TGZn2ivJ8Jzp3Lzx5W9d3voGpZwzDun7mxJJJaediCBVu+Z56ORoz/RXaLrVCVU gjQyO9lgwzObTvx+zVJ0F7znVr7UEogZnw8TOI2Ks/XuqXvJa8/kxPUk5WkjWvB/XJ7s bqu09yW88y+cyfc6Jrh1foHjTpdpmt4Q3eO1sWYXeSaFrHGs0g2eyOzjTXWZnMtEJ1+J 1G+6iqUCdnABtwHnP19XxKVtqb6HDYYqRhpdKqpWHwn0Zab3nPZJXi4czlb29jK0Gjrl ITkw== |
|
Hi,
I have a question regarding speculated preallocation in XFS, w.r.t kernel version: 3.16.0-46-generic. I am using Swift version: 1.0 and mkfs.xfs version 3.2.1
When I write a 256KiB file to Swift, I see that the underlying XFS uses 3x the amount of space/blocks to write that data. Upon performing detailed experiments, I see that when Swift uses fallocate (default approach), XFS doesn't reclaim the preallocated blocks that XFS allocated. Swift fallocate doesn't exceed the body size(256 KiB). Interestingly, when either allocsize=4k or when swift doesn't use fallocate, XFS doesn't consume additional space. Can you please let me know if this is a known bug and if its fixed in the later versions? Thanks & Regards, Dilip
|
| <Prev in Thread] | Current Thread | [Next in Thread> |
|---|---|---|
| ||
| Previous by Date: | [PATCH 3/3] xfs: fold xfs_vm_do_dio into xfs_vm_direct_IO, Christoph Hellwig |
|---|---|
| Next by Date: | Re: [RFCv4 00/76] xfs: add reverse-mapping, reflink, and dedupe support, Darrick J. Wong |
| Previous by Thread: | VFS/XFS: directio updates to ease COW handling, Christoph Hellwig |
| Next by Thread: | Re: Request for information on bloated writes using Swift, Eric Sandeen |
| Indexes: | [Date] [Thread] [Top] [All Lists] |