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SORRY! I should have posted this under the hardware forum....
I need someone to please point me in the right direction with this...
I'm using a supposedly nice graphics card under Ubuntu 9.10, an Asus GeForce GTS 250 1GB Dark Knight, and I think I'm getting a poor performance out of it. I realized this when "backing up" some movies I have on DVD and took more than 30 min with k9copy for each DVD.
The CPU is a AMD Phenom II 955 X4 Quad Core 3.2Ghz Black Ed. 125W AM3. Which I think is powerful enough for not to be a bottleneck.
Maybe there is nothing wrong with the graphics card and the bottleneck is somewhere else...
I provably should benchmark my system to find out if I'm not taking advantage of my hardware. I've seen phoronix has a test suite. Any other recommendations?
In case someone is curious here my lsmod output...
yooy is right. Your bottleneck lies elsewhere, like:
- disk I/O: check using some simple 'dd' commands to test read/write:
$ sudo time sync;sync;dd if=/dev/zero bs=1024 count=10000000 of=/vm2/10Gb.file;sync;sync
...flushes writes to disk twice, writes 10GB file, followed by two more flush-to-disk, obviously change the destination to suit your enviro
....you wanna see 100MB/sec or better in my opinion, but you can get away with around 80MB/sec.
- can also use hdparm to get some performance numbers:
$ sudo hdparm -tT /dev/sda
- what is the filesystem type? I prefer XFS for my media PC / fileserver's data volume which hosts DVD's in ISO format that I stream over my home network and over wireless. I mount XFS with '-noatime' argument on top of a RAID0 stripe across 2 1TB SATAII 7200 speed harddrives. I get around 100--130MB/sec disk write speed. My bottleneck is the controller and spindle speed.
- You can tweak things with 'hdparm' & 'sdparm' but it can get dangerous fast. One thing I did, disabled read cache via this on both disks:
$ sudo sdparm -s RCD=1 -S /dev/sdb
$ sudo sdparm -s RCD=1 /dev/sdb
....and then disable write-cache:
$sudo hdparm -W 0 /dev/sdb
...and turn off read-lookahead:
$ sudo hdparm -A0 /dev/sdb
**NOTE!!: before tuning, backup your data! Also change one thing at a time and then test read/write speed.
- check you total RAM versus swap using 'free -m' and 'vmstat'. vmstat should report total amt of swapping since last reboot. You want to have a swap size at minimum 1.5 times total RAM.
- could also be CPU gettin hit hard...check 'top' and 'vmstat'
Very interesting, these are the kind of things I was hoping to get to learn with linux!
Here are some results:
Quote:
Originally Posted by fuubar2003
$ sudo time sync;sync;dd if=/dev/zero bs=1024 count=10000000 of=/vm2/10Gb.file;sync;sync
....you wanna see 100MB/sec or better in my opinion, but you can get away with around 80MB/sec.
At 11,9 MB/s a DVD could be copied in about a little less than 6 min.
Quote:
$ sudo hdparm -tT /dev/sda
Code:
Timing cached reads: 7478 MB in 2.00 seconds = 3741.04 MB/sec
Timing buffered disk reads: 396 MB in 3.01 seconds = 131.40 MB/sec
Are these good values?
Quote:
what is the filesystem type?
The file system is ext4, could this have a big impact in performance?
Quote:
- You can tweak things with 'hdparm' & 'sdparm' but it can get dangerous fast.
I'll try this later, but I'm thinking I have some bigger bottleneck than the hard drive writing speed right now.
Quote:
- check you total RAM versus swap using 'free -m' and 'vmstat'.
While decrypting the movie the total amount of swap space is 0 mb.
Quote:
Could also be CPU gettin hit hard...check 'top' and 'vmstat'
k9copy opens four processes some of which reach up to 90% cpu usage sometimes but stay at 90 very short and then drop down to 30% or 50%.
I have some AMD power saving technology that keeps CPU frequency low when needed. Most of the time is at 800 MHz and but when one of the CPU's usage kicks to 90%, it changes to 3.20GHz and quickly goes back.
It doesn't seem that the CPU is getting more work that it can handle.
I'm out of ideas... You said the GPU doesn't get much work from decrypting movies. I can't figure out where the bottleneck is...
- 11MB/sec ....you might need to test that read with a larger file to see if your speed increases the more is read or not. Might try a different cd/dvd drive each 1x of speed is around 1.3MB/sec. If you have a 24x speed rom drive that might help.
- Turn on DMA, that usually boosts speed. To see if it is on:
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