Project

General

Profile

Actions

Feature #2003

closed

limit XFS extent fragmentation for rbd

Added by Mark Nelson over 12 years ago. Updated almost 12 years ago.

Status:
Rejected
Priority:
Normal
Assignee:
-
Category:
librbd
Target version:
-
% Done:

0%

Source:
Tags:
Backport:
Reviewed:
Affected Versions:
Pull request ID:

Description

A user with the handle pmjdebruijn was asking earlier today about XFS extent fragmentation due to ceph writes on the freenode xfs channel. We should look into this for testing at some point.

We can use xfs_bmap to examine the extent ranges. Sample output from the user is here:

http://pastebin.com/xABVh19J

Suggestions from Christoph Hellwig are to use 512 byte inodes and set rbd_writeback_window to a large value. Sounds like typically there should be no more than 2-3 extent ranges for files of that size and the user is seeing 8.


Related issues 1 (0 open1 closed)

Related to Ceph - Feature #2052: librbd: cachingResolvedJosh Durgin

Actions
Actions

Also available in: Atom PDF