Longtime lurker registering since I've actually got a reason to post now.
Quick system summary: Old Intel BX motherboard, 512MB memory, P3-700 (100MHz fsb), winxp pro, 3ware 7810 with 2xWD1200AB, 2x 120GB Maxtor D540X and 4x 120GB Maxtor DM+9 (3 of them brand new) in raid-5, highpoint rocket133 with a lonely wd2000BB and a 3com nic.
First as basic disk:
and then as dynamic disk:
So, going from dynamic disk helped a bit on my ATTO scores. Didn't impove my realworld scores at all though. Read speeds are great, but the problem is sloooow write speeds. I know the 7810 isn't optimized for raid-5 performance, but surely more then 4-5MB/sec should be feasable when copying from the other controller or the network. Although I am running a mix of disks, some 5400rpm and some 7200rpm, would that impact performance this much?
Reading from the raid to either network mounts or the other controller yields great speeds (maxes out the other disk or the nic), but anything writing to the raid is extremely slow. Using perfmon to monitor transfer speeds I get an average of ~4.5MB/sec when copying to the array. Interestingly enough, doing two or three copies to the array at the same time increases speeds by almost 2MB/sec per thread (increasing outstanding I/Os thereby increasing total throughput?). When running three copying threads I get ~8MB/sec and my aging P3-700 is pushing 90% or so, so the CPU is really struggling.
I've tried running w2k, since some people on this board have had better performance running that. For me though the difference was absolutely zero. Another thing I've noticed is that when "pulling" files to the raid volume over the network I get a steady stram of data, while "pushing" data I get a rapid peak<->nothing oscillation (maxtor sawtoothing? at those speeds? and no promise controller in sight?). This occurs in both win2k and winxp.
Latest firmware and drivers for the 3ware are installed, and write-caching is enabled. No extra processes are running in the background and only one process reads or writes to the disk at a time.
So, my question is: How to increase my write performance?
Things I've though of so far:
1. Replace the motherboard + cpu with something more up-to-date. A 1.8GHz P4 based thingy, or an AMD-760 MP motherboard (for a nice 64-bit pci bus) is an option.
2. Replace the WD disks, since people don't really hold them in high regard when it comes to raid performance. Maybe they're holding the array back in some way.
3. Upgrade the 3ware card to a 7500-8.
4. Live with it. I'm mostly going to be reading from the array anyways. Still annoying though.....
Any hints/tips would be greatly appreciated.