anyone using an SSD under Arch? Please post a quick benchmark

graysky · 2009-08-09 19:43:35

I'm considering an SSD for my Linux root and /home. If you're using an SSD under Arch, can you please run a quick benchmark for me and post the results in this thread? You can use hdparm to do a quick read test. Here is an example using my HDD.

# hdparm -Tt /dev/sda

/dev/sda:
 Timing cached reads:   14500 MB in  2.00 seconds = 7258.88 MB/sec
 Timing buffered disk reads:  368 MB in  3.01 seconds = 122.16 MB/sec

Beyond that, have you noticed any substantial speed ups over an HDD, like launching programs, booting the system, etc.

schuay · 2009-08-09 20:11:13

/dev/sda:
 Timing cached reads:   7034 MB in  2.00 seconds = 3518.95 MB/sec
 Timing buffered disk reads:  610 MB in  3.00 seconds = 203.21 MB/sec

Intel X25-M 80Gig

Haven't done any tweaking though, still using default Arch settings.
Boot and loading apps is very noticeably faster. And Windows VMs boot in record time

graysky · 2009-08-09 21:01:14

Thanks for the info... I'm kinda surprised by the cached reads.... how can my HDD be double that of your SSD?

Last edited by graysky (2009-08-09 21:01:26)

schuay · 2009-08-09 21:08:02

Repeated the runs without KDE running, this time I got a consistent 4684 MB/s cached and 228 MB/s buffered disk reads.

No idea about the cached reads..

Ranguvar · 2009-08-10 01:46:57

Noop scheduler should help, if you'd like to try it

Add elevator=noop to the kernel CLI. Unless you also have hard drives, in which case you can do `echo noop > /sys/block/$devicename/queue/scheduler` to set only a particular device. I think there's a way to set it every boot, but I forget.

Last edited by Ranguvar (2009-08-10 01:58:33)

keenerd · 2009-08-10 03:24:06

Transcend class 6 micro SDHC:
Timing cached reads: 558 MB in 2.00 seconds = 278.60 MB/sec
Timing buffered disk reads: 46 MB in 3.05 seconds = 15.06 MB/sec

Sandisk Ultra II CF-IDE:
Timing cached reads: 410 MB in 2.01 seconds = 204.58 MB/sec
Timing buffered disk reads: 44 MB in 3.02 seconds = 14.56 MB/sec

Oh, homebrew SSDs. You are relatively slow, but absolutely cheap.

edit: looking at the man page, you are supposed to do this test with little or no CPU activity. That does not exactly match the conditions of my tests.

By the way, the "-T" test has very little to do with what sort of drive you have, and is entirely CPU based. Does the ratio of the two mean something?

Last edited by keenerd (2009-08-10 03:28:13)

litemotiv · 2009-08-10 08:06:52

hdparm is a clinical test, nowhere near being a good indicator for real life results.

ssd's main strengths are < 0.1ms accesstime, great random read performance (no moving head), low power usage and they're shockproof; get a benchmark that tests that and you'll see different results.

if you spend your days copying gigs of data all the time, get a hdd.

lilsirecho · 2009-08-10 16:05:02

Perhaps use of IDE-MODE flash devices will provide best answers with the hdparm measure. It does a sequential test which is hardly normal for operating systems.

Usual performance from ide mode flash devices is 45mb/sec but in practice may be a bit less in hdparm. Two ide mode flash drives in raid0 give me less than 90 mb/s. My use is for quick access storage, mostly read-only. When first installed, 90 mb is possible but within a few weeks, it lessens to the mid 80"s even with read-only.

The performance over time lessens if the units are used as SSD and such is normal wear and tear. Many articles cover the subject and the methods used to minimize the effects.

Much is going forward with SSD and expectation is that in a few years they will be in wide use. This remains to be seen!

You may be aware of all so excuse my oops!

graysky · 2009-08-10 20:34:50

litemotiv - you make a good point: perhaps hdparm isn't the best choice. I guess I wanna know that I'll really see a difference by locating my / partition on an SSD vs. HDD speed wise. If I do it, I plan to keep /var and /home on the HDD.

Last edited by graysky (2009-08-10 20:35:16)

Misfit138 · 2009-08-10 20:52:06

Ranguvar wrote:

I think there's a way to set it every boot, but I forget.

add

elevator-noop

to the kernel line in GRUB...?

schuay · 2009-08-11 03:22:35

graysky wrote:

litemotiv - you make a good point: perhaps hdparm isn't the best choice. I guess I wanna know that I'll really see a difference by locating my / partition on an SSD vs. HDD speed wise. If I do it, I plan to keep /var and /home on the HDD.

I went with / and /home on the SSD, plus a HD mounted on /home/me/Data with various symlinks for convenience. Works very well for me.

Ranguvar · 2009-08-13 19:29:53

Misfit138 wrote:

Ranguvar wrote:
I think there's a way to set it every boot, but I forget.
add
elevator-noop
to the kernel line in GRUB...?

I mentioned elevator=noop in my post The problem with it is that it sets the I/O scheduler for _all_ disks to Noop, and if you also use hard drives, external or not, that is undesirable.

litemotiv · 2009-08-14 11:04:42

Ranguvar wrote:

Misfit138 wrote:
Ranguvar wrote:
I think there's a way to set it every boot, but I forget.
add
elevator-noop
to the kernel line in GRUB...?
I mentioned elevator=noop in my post The problem with it is that it sets the I/O scheduler for _all_ disks to Noop, and if you also use hard drives, external or not, that is undesirable.

deadline is also an excellent scheduler for ssd's

Arch Linux

#1 2009-08-09 19:43:35

anyone using an SSD under Arch? Please post a quick benchmark

#2 2009-08-09 20:11:13

Re: anyone using an SSD under Arch? Please post a quick benchmark

#3 2009-08-09 21:01:14

Re: anyone using an SSD under Arch? Please post a quick benchmark

#4 2009-08-09 21:08:02

Re: anyone using an SSD under Arch? Please post a quick benchmark

#5 2009-08-10 01:46:57

Re: anyone using an SSD under Arch? Please post a quick benchmark

#6 2009-08-10 03:24:06

Re: anyone using an SSD under Arch? Please post a quick benchmark

#7 2009-08-10 08:06:52

Re: anyone using an SSD under Arch? Please post a quick benchmark

#8 2009-08-10 16:05:02

Re: anyone using an SSD under Arch? Please post a quick benchmark

#9 2009-08-10 20:34:50

Re: anyone using an SSD under Arch? Please post a quick benchmark

#10 2009-08-10 20:52:06

Re: anyone using an SSD under Arch? Please post a quick benchmark

#11 2009-08-11 03:22:35

Re: anyone using an SSD under Arch? Please post a quick benchmark

#12 2009-08-13 19:29:53

Re: anyone using an SSD under Arch? Please post a quick benchmark

#13 2009-08-14 11:04:42

Re: anyone using an SSD under Arch? Please post a quick benchmark

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