4 Attachment(s)
Striker II Formula w/SIX Drive RAID-0
Well folks - I've read through the whole thread, and I'm now caught up. WeStSiDePLaYa, I feel I know you pretty well now, haha. I've gleamed a lot of OC ranges, taken in a lot of good info (and I thank you all) and plan on starting my own OC endeavor soon. For now, tho, I have something to contribute.
Some of you will say "WTF" to this setup, and others will treasure every last scrap of data I'm about to offer here. Specifically, while you guys were testing the OC limits, I've been hammering the RAID controller on the 780i Striker board. I'll get right to it.
I'm greedy - not only do I want a triple-SLI and a decently OC'd quad, but I wanted to drastically increase my hard drive performance (game load times). So, I opted for a 6-drive RAID-0. Don't start a preaching session about the dangers of RAID-0 (seriously, XtremeSystems is not a place for conservatives). My ultimate goal: Find the absolute best stripe, cluster and settings for the fastest overall RAID-0 setup on the Striker II.
My test setup:
- 6 x Western Digital SE16 320gb (RAID-0)
- ATTO, Length=4mb Size=1024kb
- HDTach, short bench
- 15gb partition (edge of disk)
- Sector hex edit (start on sector 3072 instead of 63. More on this later)
- 8, 16, 32, 64, 128k RAID stripe size tests
- 4, 16, 32, 64k windows file allocation/format size (aka cluster) tests
Findings:
Attachment 73551
You can see that if You're up for 128k stripe and 64k cluster, you can achieve 1gb per sec read speeds when accessing files over 1mb in size! Even higher with one more tweak (more below).
If you look closely at the same 128k+64k table, tho, you'll see horrible read speeds with files under 128kb in size. Which is understandable; the read/write duration is pretty long at 128k+64k, so there is a lot of wasted effort from the drives on small files at these settings.
So, how to determine the best balance? I scoured a windows install, complete with games, to get a sense of how big and how many files we load on average. I decided to take the following sample file numbers, and create a read/write time simulator:
20,000 x 4kb files
5,000 x 16kb files
10,000 x 128kb files
4,500 x 1mb files
Basically, the time simulator would estimate how long it would take to read that many files of each file range, add them up, and point out the quickest one on average.
Time simulator matrix:
Attachment 73552
Results (lower is better):
Attachment 73553
Suggestions:
A. Your time is spent on your comp playing a handful of specific games. You do not use your machine for work, video digitizing, processing large quantities of files. Suggested settings on 6-drive array: 64k stripe, 32k cluster. Parition your C: separately at 4k cluster.
B. Or, you want to maintain a balance of read and writes (you like to use your comp for things other than games, and/or you cycle your games often, trying new things). Suggested settings: 32k stripe, 32k cluster.
C. Or, you want to keep your games on the same parititon as your Windows install, and have balanced read/writes. Suggested settings: 32k stripe, 4k cluster.
D. You do like to play games, but you'd rather tweak the speed to its maximum processing of large files (moving TV shows around, editing, capturing video, etc.. anything with large amounts of large files, especially swap files). Consider 64k stripe, 64k cluster. But emphasis on capturing (writing) will actually benefit from 64k stripe 32k cluster better.
Limitations to consider before starting:
1) Windows XP will only allow you 'install' on a 4k cluster format (I even tried Acronis image restore, can't get it to boot). So you may wish to do 32k/4k for a C: partition, and a 32k/32k for the remainder, and install your games on the second partition.
2) Do not use drives larger than 320gb, or you will end up hitting the 32-bit drive space addressing problem that limits you to 2tb.
3) Your first partition will be the fastest (closest to edge of disk), so if you were really anal, you should create a parition for your games, and THEN your C: parition.
Other Interesting Notes and Enhancements:
1) 3072 sector hack. I'll give the short version, and then if anyone's interested, I can walk you through it. I found that Windows' (XP and older only) first partition starts at sector 63, and I had read that it is incredibly crappy for RAID (any kind) performance. This is due to the fact that when data is writing to the drives, the write durations can never be fully synchronized across all the drives; your comp will always write in 4k chunks (for example) so it will often have to pick up the head and move to another location to finish writing the file, on at least the first drive. You can manually adjust a newly created partition to start at a multiple of your stripe size x width, and the performance increases no less than 12% avg. Inquire if interested!
2) Disabling NCQ. I was surprised to find that this helped increase average speeds up to 9%. Once you've installed your OS, go under your device settings, select each of the three nVidia RAID controllers (Port 0 & 1 tabs) and uncheck the "Enable command queuing". Click "no" to the restart option, until you're done your last.
3) Contrary to what you might read out there on the subject, disabling your Write Cache WILL cripple your drive speeds.
4) My particular time simulator is bias towards equal read and writes. You may find your usage warrants more emphasis on reads than writes. If you would like, I can send you the time simulator spreadsheet, and you can edit the number of files in the simulator.
Attachment 73554
-Wiinter
Rig:
Asus Striker II Formula 780i
Intel Q6600 Kentsfield
2 x 1gb Crucial Ballistix PC8500
2 x XFX 8800GTX SLI
6 x Western Digital SE16 320gb (RAID-0)
(4tb alternate storage & backup)
Silverstone Olympia OP1200 (1200w single rail)
WTB one used XFX 8800GTX (575mhz)