Gentoo Archives: gentoo-user

From: "Marc Stürmer" <mail@×××××××××××××.de>
To: gentoo-user@l.g.o
Subject: [gentoo-user] Btrfs: how to fix slow sequential write performance?
Date: Wed, 25 Sep 2013 08:54:52
1 Greetings fellow Gentooistas,
3 at the moment I am doing some testing and evaluating of Btrfs on my own
4 system. Why? Just because I can and I am curious about it.
6 Because I am doing that for evaluation purpose please don't give advise
7 like "go ZFS" or something like that, thank you.
9 Kernel is 3.10.7, the file system is on one hard drive only (SATA).
11 And here comes my question: sequential write access seems to be slow as
12 hell, actually something around like 10 Mbyte/s according to dd's output.
14 The same HDD performed under ext4 with around 90 Mbyte/s.
16 Command is something like: dd if=/dev/zero of=file.img bs=1G count=150
18 Nothing else is running at the time of writing, no scrub/balance on the
19 file system or other process eating up much cpu time.
21 Mount option is "relatime" only. So is this a well known issue only with
22 this kernel or generally with this file system at the moment?
24 Are there any possible fixes to squeeze better performance out of it or
25 is this unlikely to happen so that I should better take that into
26 account of my evaluation and maybe dump it then?
28 Thanks in advance.


Subject Author
Re: [gentoo-user] Btrfs: how to fix slow sequential write performance? William Kenworthy <billk@×××××××××.au>