From mboxrd@z Thu Jan 1 00:00:00 1970 From: Miao Xie Subject: Re: Poor creat/delete files performance Date: Wed, 18 Aug 2010 19:00:56 +0800 Message-ID: <4C6BBD68.5040408@cn.fujitsu.com> References: <4C6BB21E.3000809@cn.fujitsu.com> Reply-To: miaox@cn.fujitsu.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: Chris Mason , Yan Zheng , Linux Btrfs To: Leonidas Spyropoulos Return-path: In-Reply-To: List-ID: On Wed, 18 Aug 2010 11:49:16 +0100, Leonidas Spyropoulos wrote: > Have you tried umounting and mounting before the second test to > eliminate any caching? Yes, I have done it. The result is similar to the one I have reported. (Unit: second) Create file performance BtrFS Ext4 Total times: 2.484392 1.505082 Average: 0.000050 0.000030 Delete file performance BtrFS Ext4 Total times: 3.369469 1.024886 Average: 0.000067 0.000020 > Which kernel you use? v2.6.35 Regards Miao Xie > > 2010/8/18 Miao Xie: >> Hi, >> >> We did some performance test and found the create/delete files performance >> of btrfs is very poor. >> >> The test is that we create 50000 files and measure the file-create time >> first, and then delete these 50000 files and measure the file-delete time. >> (The attached file is the reproduce program) >> >> The result is following: >> (Unit: second) >> Create file performance >> BtrFS Ext4 >> Total times: 2.462625 1.449550 >> Average: 0.000049 0.000029 >> >> Delete file performance >> BtrFS Ext4 >> Total times: 3.312796 0.997946 >> Average: 0.000066 0.000020 >> >> The results were measured on a x86_64 server with 4 cores and 2 SAS disks. >> By debuging, we found the btrfs spent a lot of time on searching and >> inserting/removing items in the ctree. >> >> Is anyone looking at this issue? >> >> Regards >> Miao Xie >> > > >