new SSD installed, some questions

ssl6 · 2011-01-28 12:44:54

i got a 40gb Corsair force last week. so far its quite nice, i have definitely noticed a performance increase in loading times.

essential what i had before was a hard drive with 3 partitions for /boot, / and /home, so i opted to leave it in tact and the SSD is / only with /boot and /home on the hard drive still, i figured in case of failure, i still have an OS that way

now before setting it up, i spent some time researching more up to date options for fine tuning SSD's, and also found we have a rather useful guide on the forum here now too. the last time i installed to an SSD was my eee 900a with a 4gb ssd, that terribly slow thing they put in there.

I was going to use ext2 until i read that ext4 with no journal is the better option with trim support now, so thats fine, i'm glad i read up first

i also made sure my sata controller is set to ahci and modified grub for that as well, and i'm also using the noop scheduler for the ssd only as you can see from some of my output below. what im wondering about, is the read performance from hdparm, seems a little low, i could understand if i was using an older system, but i'm running an Asus M4A79t, 8gb DDR3, and phenom X4 955. my SSD is the sdd device here, its on my 4th sata port, there's three 1TB drives from sda-sdc

[urmom@urmom-pc ~]$ hdparm -tT /dev/sdd
/dev/sdd:
 Timing cached reads:   7604 MB in  2.00 seconds = 3803.02 MB/sec
 Timing buffered disk reads: 456 MB in  3.01 seconds = 151.64 MB/sec

[root@urmom-pc urmom]# dd if=/dev/zero of=tempfile bs=1M count=1024 conv=fdatasync,notrunc
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 10.3611 s, 104 MB/s

[root@urmom-pc urmom]# dd if=tempfile of=/dev/null bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 9.14894 s, 117 MB/s

[root@urmom-pc urmom]# dd if=tempfile of=/dev/null bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 0.315993 s, 3.4 GB/s

[urmom@urmom-pc ~]$ lspci -vnn |grep SATA
00:11.0 SATA controller [0106]: ATI Technologies Inc SB700/SB800 SATA Controller [AHCI mode] [1002:4391] (prog-if 01 [AHCI 1.0])
        Subsystem: ATI Technologies Inc SB700/SB800 SATA Controller [AHCI mode] [1002:4391]

[urmom@urmom-pc ~]$ cat /sys/block/sdd/queue/scheduler
[noop] deadline cfq

[urmom@urmom-pc ~]$ cat /sys/block/sda/queue/scheduler
noop deadline [cfq]

essentially my question is, is there maybe something better to test the performance with? and does anyone have any suggestions on what else can be done to fine tune? my /tmp is being put in ram, as well as /shm i think it is. i do need to move /var somewhere, but other than that

maybe im just dreaming and the performance i see is completely fine? but i'm lookinga the ssd benchmarking wiki page, and the corsair should be quite comparable to the ocz vertex 2, and the numbers im getting are not

Last edited by ssl6 (2011-01-28 12:53:34)

nspattak · 2011-01-28 13:54:01

Did you try the same commands on an ocz vertex 2 ?
I guess you expected to see numbers similar to those published on tech report etc. Your benchmarks are totally different. try iozone or bonnie++

ssl6 · 2011-01-28 17:23:06

we have number published on the ocz vertx on the wiki, https://wiki.archlinux.org/index.php/SS … ERTEX_60gb

mine should be comparable according to other BM's and hardware specs, and they're waaay below

edit/// i may have been lookin at the wrong numbers....i guess thats what happens when you stare at a screen all day....

Last edited by ssl6 (2011-01-28 17:25:54)

zenlord · 2011-01-29 10:54:47

Did you follow a guide to do all those tweaks? I'm expecting an SSD to be delivered in the next few weeks and am preparing to install arch on an OCZ Vertex2 40GB...

cubeist · 2011-01-30 00:41:38

Those numbers are low. The specs say you should get ~270-280MB/s, and most SSD's get very close to the published specs when new.
A couple thoughts:

-In your fstab line, make sure you have "noatime" as an option(some people use relatime, you can google the difference, most agree on noatime for ssd's).
-Did you align the blocks before installing? Even with garbage collection and TRIM this is still a very important step to maximize SSD performance. There are lots of pages about aligning. Here are a couple to get you started
http://www.nuclex.org/blog/personal/80- … d-on-linux
https://wiki.archlinux.org/index.php/SS … erformance
http://thunk.org/tytso/blog/2009/02/20/ … lock-size/

Edit
FYI - when I aligned my SSD, the GPT method and switching to GRUB 2 as outlined in the arch wiki caused all sorts of problems. Using MBR with cfdisk (or fdisk) worked very well. (YMMV)

Last edited by cubeist (2011-01-30 00:45:40)

ssl6 · 2011-01-31 12:04:14

i did follow the guide on the wiki. the noatime is in fstab as well as the other command for trim that i forget what its called off hand. but i was looking at the wrong numbers, i'm pretty sure from the dd bench numbers i have, their comparable to the numbers on the wiki, so i should be all set, the system feels bloody fast, so i'm pretty sure its all good.

its not my first time setting up an ssd either, i've had my netbook with a 32gb runcore ssd for some time now, but this new drive in my tower i setup a little different due to it having trim support.

@zenlord, i'm quite sure you'll like the SSD. everything loads bloody fast now, i'm running KDE4, and for the most part, i click on something, and its open, even larger apps hardly take 2 seconds

Arch Linux

#1 2011-01-28 12:44:54

new SSD installed, some questions

#2 2011-01-28 13:54:01

Re: new SSD installed, some questions

#3 2011-01-28 17:23:06

Re: new SSD installed, some questions

#4 2011-01-29 10:54:47

Re: new SSD installed, some questions

#5 2011-01-30 00:41:38

Re: new SSD installed, some questions

#6 2011-01-31 12:04:14

Re: new SSD installed, some questions

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