You are not logged in.

#1 2009-05-02 15:51:34

baetis
Member
Registered: 2009-05-02
Posts: 5

[Solved - ext4 is just super slow] New Install Seems Very Slow

After 8 years of Gentoo I decided to replace my main development box with Arch.  No X, just screen, emacs, w3m, and various compilers/languages.

My old box is a 5 year old Gentoo box.  AthlonXP 2200 (1.7Ghz), 512M.

The new Arch box is a based on a Shuttle K48.  It's got an Intel E2200 (Dual Core, 2.2Ghz), 2G, new SATA drive.

Just to see I did a clean checkout of Clojure (a new JVM language) and did a "ant" on both boxes.

Gentoo: 20 Seconds

Arch: 51 Seconds

I don't think it's a Java issue (same JVM version btw), it's just the only thing I can really think to compare it against.  When Arch hits the compile step I hear a fan go off and my hard drive light stays on for the durations.    I used ext4 on the drives, gentoo is using reiser.  Nothing else seems particularly slow, but I'm not doing anything on it really like I said.  A pacman install will happen almost instantaneously (which after 8 years of Gentoo is a welcome change).

Anyone have any ideas?  I'll post whatever info you think might be useful.

Thanks.

Last edited by baetis (2009-05-02 16:02:40)

Offline

#2 2009-05-02 16:01:06

eldragon
Member
From: Buenos Aires
Registered: 2008-11-18
Posts: 1,029

Re: [Solved - ext4 is just super slow] New Install Seems Very Slow

hmm, cpu scaling governor?

Offline

#3 2009-05-02 16:01:48

baetis
Member
Registered: 2009-05-02
Posts: 5

Re: [Solved - ext4 is just super slow] New Install Seems Very Slow

Ah, solved, sort of.  I copied the compojure directory over to my boot partition which is ext2 and now the compile takes 18 seconds.  So, whats up with ext4?  Guess I'll reinstall with ext3 and see how that does.

Thanks.

Last edited by baetis (2009-05-02 17:03:14)

Offline

#4 2009-05-02 18:35:39

baetis
Member
Registered: 2009-05-02
Posts: 5

Re: [Solved - ext4 is just super slow] New Install Seems Very Slow

So I reinstalled with reiserfs so the comparison would be against the same filesystem type.  The compile time on arch is now down to 20 seconds.  It still doesn't make sense though.  The compile is using 2 2.2Ghz cores, it should be crushing my old Gentoo box.

I might try again with ext3.

If anyone is curious if their ext4 shows similar issues try this (you'll need 15M on an ext2 /boot partition):

On an ext4 partition:
pacman -S svn
pacman -S jdk
pacman -S apache-ant
svn checkout http://clojure.googlecode.com/svn/trunk/ clojure
cd clojure
ant [take note of time]

As root:
cd /boot
cp -R <path to where you checked out clojure> .
cd clojure
ant clean
ant [compare times]

Do it a few times, ant clean then ant on both partitions and see how you fare.

Offline

#5 2009-05-02 20:24:45

iBertus
Member
From: Greenville, NC
Registered: 2004-11-04
Posts: 2,228

Re: [Solved - ext4 is just super slow] New Install Seems Very Slow

Perhaps this compile process is limited by something other than CPU speed. Obviously, your new box has much more processing power than the previous Gentoo one, however, I would bet it's either I/O limited for isn't making use of multiple cores.

Also, did you disable barriers in ext4. I've seen a few threads around which claim that using barriers makes ext4 unsable.

Last edited by iBertus (2009-05-02 20:25:24)

Offline

#6 2009-05-02 21:33:43

bender02
Member
From: UK
Registered: 2007-02-04
Posts: 1,328

Re: [Solved - ext4 is just super slow] New Install Seems Very Slow

I'd think it's IO limited. Try mounting a directory with tmpfs (ie as a ramdisk) and compile there.

Offline

#7 2009-05-02 21:59:12

baetis
Member
Registered: 2009-05-02
Posts: 5

Re: [Solved - ext4 is just super slow] New Install Seems Very Slow

On a tmpfs it's 16 seconds on Gentoo, 18 on Arch.

Even it was IO, I would think the new arch box with a brand new SATA drive would still significantly out perform the Gentoo box with its IDE ATA/133.

Thanks for the continued suggestions.

Offline

Board footer

Powered by FluxBB