SSD RAID

[LavCat]

I could necro any number of old threads to ask my questions, but I thought a new topic might be more polite.

For the past year or two I have happily been using an Intel X25-V SSDSA2MP040G2R5 for WoW. Then came 4.1 this week and that was the end of that. When Cataclysm hit there was a workaround of patching on a different disc, then copying back to the SSD. With 4.1 the patch and copy process works, WoW.exe even runs, but the launcher refuses to do anything, giving an "Insufficient space" error.

A blue post suggested deleting the data/cache folder as a workaround, but that was a terrible idea. Yes, the launcher is then happy but the play experience is unaccetable.

Buying a new, large, high-end SSD is not financially attractive. I had thought to perhaps pick up a second Intel X25-V SSDSA2MP040G2R5 and run the two drives in RAID 0. Unfortunately the Intel X25-V SSDSA2MP040G2R5 is obsolete and unavailable from mainstream online sources. I located stock in Latvia and China -- and even some in the US, but not at reasonable prices.


Hence, my questions:

How identical do drives have to be for RAID? My only experience with RAID is using RAID 1 with identical drives. Specifically could I get an Intel 320 Series SSDSA2CT040G3K5 and use it in RAID 0 with my existing Intel X25-V SSDSA2MP040G2R5? They have the same controller chip and same nominal capacity. My motherboard has RAID support but I was thinking to make a Windows 7 striped volume. My understanding is that for RAID 0 setups the drives do not have to be identical.

Any other thoughts?

[Lissa]

I could necro any number of old threads to ask my questions, but I thought a new topic might be more polite.

For the past year or two I have happily been using an Intel X25-V SSDSA2MP040G2R5 for WoW. Then came 4.1 this week and that was the end of that. When Cataclysm hit there was a workaround of patching on a different disc, then copying back to the SSD. With 4.1 the patch and copy process works, WoW.exe even runs, but the launcher refuses to do anything, giving an "Insufficient space" error.

A blue post suggested deleting the data/cache folder as a workaround, but that was a terrible idea. Yes, the launcher is then happy but the play experience is unaccetable.

Buying a new, large, high-end SSD is not financially attractive. I had thought to perhaps pick up a second Intel X25-V SSDSA2MP040G2R5 and run the two drives in RAID 0. Unfortunately the Intel X25-V SSDSA2MP040G2R5 is obsolete and unavailable from mainstream online sources. I located stock in Latvia and China -- and even some in the US, but not at reasonable prices.


Hence, my questions:

How identical do drives have to be for RAID? My only experience with RAID is using RAID 1 with identical drives. Specifically could I get an Intel 320 Series SSDSA2CT040G3K5 and use it in RAID 0 with my existing Intel X25-V SSDSA2MP040G2R5? They have the same controller chip and same nominal capacity. My motherboard has RAID support but I was thinking to make a Windows 7 striped volume. My understanding is that for RAID 0 setups the drives do not have to be identical.

Any other thoughts?

If you go with JBoD instead of RAID, it doesn't matter (JBoD is sorta like RAID 0, but the data isn't equally spaced across the disks).

[LavCat]

If you go with JBoD instead of RAID, it doesn't matter (JBoD is sorta like RAID 0, but the data isn't equally spaced across the disks).

I was thinking RAID 0 with these drives would give much better game performance, though, as tested by Anand:

http://www.anandtech.com/show/3618/intel...g2-for-250


In any event I did not have the courage of my convictions, and not being able to find the same drive as I have, I ordered an 80 GB one that maybe will be able to run WoW until the next expansion.

[Taem]

When I first made my 3rd computer (not anything recent), I made it with four drives using RAID 10. All the manuals said to make sure they were not only the same size drive, but the same drive. I didn't care and partitioned my 500-GB IDE in two, and popped in two more 250-GB IDE drives, one Western Digital, and the other two different models. It had issues from the get-go, but seemed to work fine for a few months. Then, for whatever reasons, my IDE drives slowly went out one at a time until none of them worked any longer and I ended up get getting a Sata drive. Go figure. Either it was time (destiny), or you really should have the same drive and same size, lol.

P.S., when I say went out, I mean totally unusable and unrecoverable. I have no idea what happened to them. I let my kids take them out back and smash them to bits with hammers to see what was inside a HD.

[--Pete]

Hi,

I let my kids take them out back and smash them to bits with hammers to see what was inside a HD.

Mommas don't let your babies grow up to be particle physicists, smashing it all to see what's inside.



--Pete

[kandrathe]

If you go with JBoD instead of RAID, it doesn't matter (JBoD is sorta like RAID 0, but the data isn't equally spaced across the disks).

I was thinking RAID 0 with these drives would give much better game performance, though, as tested by Anand:

http://www.anandtech.com/show/3618/intel...g2-for-250


In any event I did not have the courage of my convictions, and not being able to find the same drive as I have, I ordered an 80 GB one that maybe will be able to run WoW until the next expansion.

Ok, some thoughts even though you seem to have solved the current dilema... Additional information would help. What are your other constraints, such as, is this a laptop? What is the Mobo/raid controller?

Hardware vs Software Raid -- If you are relying on hardware raid controller, you should be able to consult the controller's manual for requirements (which still may be bendable). It would be more important on hardware raid to ensure the components be more similar, (e.g. seek time, size, and throughput). If you are using Software raid (interrupt driven), then I think the OS would be more forgiving of slight differences. You are using CPU to create a logical RAID volume from two logical disk volumes, and most systems these days are not CPU bound. The volumes would need to be the same size, but theoretically they may not be the entirety of the physical volumes (e.g. Disk 1 is ~40 GB with one ~40 GB partition, and Disk 2 is ~80 GB with two ~40GB logical partitions). Slowest common denominator would be your expected timings, and if Disk 1 and Disk 2 were very different, then I'd expect other sync problems.

Also...

Barring other constraints like size and money... I'd want to have the SSD volume(s) dedicated to serving OS functions alone (i.e. logical C: ), and relegate other applications to a larger (500MB to 1TB) traditional hard disk (i.e. logical D:). One complaint I have with Microsoft OS's in general is that they make it too easy to co-mingle OS, Virtual Memory, application executables, data, cache, and temporary files all on the boot partition. It requires quite a bit of planning and discipline to keep a dedicated boot drive clear of non-OS junk (even including MS OS updates).

Then, for certain apps that may work better on SSD, I'd hack the registry to enable moving certain crucial files to the SSD volume (executables path would be the safest way, "C:\FastApps" then D: ). Thus, your application would be installed on the D:, and subsequent updates would update to D:, but you'd need to manually move the special performance executables to C:\FastApps. If the builds were consistent enough, you might even script the file copy process.

[LavCat]

Ok, some thoughts even though you seem to have solved the current dilema... Additional information would help. What are your other constraints, such as, is this a laptop? What is the Mobo/raid controller?

Hardware vs Software Raid -- If you are relying on hardware raid controller, you should be able to consult the controller's manual for requirements (which still may be bendable). It would be more important on hardware raid to ensure the components be more similar, (e.g. seek time, size, and throughput). If you are using Software raid (interrupt driven), then I think the OS would be more forgiving of slight differences. You are using CPU to create a logical RAID volume from two logical disk volumes, and most systems these days are not CPU bound. The volumes would need to be the same size, but theoretically they may not be the entirety of the physical volumes (e.g. Disk 1 is ~40 GB with one ~40 GB partition, and Disk 2 is ~80 GB with two ~40GB logical partitions). Slowest common denominator would be your expected timings, and if Disk 1 and Disk 2 were very different, then I'd expect other sync problems.

Also...

Barring other constraints like size and money... I'd want to have the SSD volume(s) dedicated to serving OS functions alone (i.e. logical C: ), and relegate other applications to a larger (500MB to 1TB) traditional hard disk (i.e. logical D. One complaint I have with Microsoft OS's in general is that they make it too easy to co-mingle OS, Virtual Memory, application executables, data, cache, and temporary files all on the boot partition. It requires quite a bit of planning and discipline to keep a dedicated boot drive clear of non-OS junk (even including MS OS updates).

Then, for certain apps that may work better on SSD, I'd hack the registry to enable moving certain crucial files to the SSD volume (executables path would be the safest way, "C:\FastApps" then D: ). Thus, your application would be installed on the D:, and subsequent updates would update to D:, but you'd need to manually move the special performance executables to C:\FastApps. If the builds were consistent enough, you might even script the file copy process.

My motherboard is an Asus M4A79T Deluxe. The raid controller is the SB750 on the motherboard. Had I gotten another Intel X25-V I was going to first try software RAID. I've never used the SB750 for RAID, but I've had less than good results from cheap motherboard RAID hardware in the past.

In general I need all the CPU cycles I can get, but my logic is that if a thread is waiting for data, it's probably not doing that much processing.

Unlike cost, size is not much of a constraint. I have ten 5 1/2 inch drive bays. Which sounds like a lot, though I had to retire an older Seagate Hawk 50-pin SCSI drive to fit the new Intel 320 Series SSD. (I do have a free drive bay but I don't have any SATA cables long enough to reach it.)

My C: drive is my DOS partition (in addition to my Windows 7 system partition and XP boot partition). My Wasteland loading time and framerates are sufficient as they are. I see no point to using SSD for my Windows 7 boot partition either. For one thing I don't trust SSD reliablity as yet. The Cheetah 15K drives do well enough for Windows. Likewise for my non-WoW application partition.

What I might try is using the now surplus Intel X25-V as the paging drive. This seemed counter intuitive to me since the Intel X25-V write times are abysmal. However I recently came across a Microsoft blog post on Windows that said paging usage was forty times more reads than writes. The Microsoft person added: "In fact, given typical pagefile reference patterns and the favorable performance characteristics SSDs have on those patterns, there are few files better than the pagefile to place on an SSD." My paging volume is on another 15K Cheetah that most probably beats the Intel X25-V on writes, but the Intel X25-V should clearly win on reads. Reliablity of my paging drive is not an issue. I could then repurpose that Cheetah or save it for a backup.

I can report that so far the new Intel 320 Series has been a complete success for WoW.

As a quondam scientist/engineer I love to tinker, and I continue to look for ways to push WoW to 60 FPS. Ways that don't involve a lot of cost. My 720 BE is a dud for overclocking. While it is perfectly stable at stock it crashes within a day at the slightest CPU overclock. Extra voltage does not seem to help. (However the L3 cache overclocks quite well.) Perhaps when Bulldozer comes out the price of Thuban will come down and I can get an upgrade.

I'd also like to get more memory. I have two 2GB sticks. I can't put in more of the same type for two reasons: the CPU cooler blocks the first two RAM sockets and the particular memory modules are no longer made. I find the subject of memory a bit complicated (at least since the days when it was core). I certainly don't want slower timings than I have. If I could find lower profile modules I might be able to stick in four. Otherwise I could opt for two 4GB modules, though these tend to not have as good timings. Another option would be to find a smaller cooler that was at least as good. Water cooling is not something I'd consider -- just ask the folks in Fukushima.

While I still welcome thoughts on RAID, at the moment RAID is academic. I think the Intel 320 Series was the best solution for me. However I'd love to hear thoughts on a memory/cooler solution that would let me use 8 gigs, preferably at fast timings. Keep in mind that this is an AMD CPU system, not Intel.

[kandrathe]

However I'd love to hear thoughts on a memory/cooler solution that would let me use 8 gigs, preferably at fast timings. Keep in mind that this is an AMD CPU system, not Intel.

Do you have room for something more vertical, such as Coolermaster Hyper 212 Plus CPU Cooler?

I don't think you've said it, what is your CPU and current RAM?

Not that you want to boost it, but I found a good article to help understand how it all works; http://www.overclockers.com/forums/showt...p?t=596023

[LavCat]

However I'd love to hear thoughts on a memory/cooler solution that would let me use 8 gigs, preferably at fast timings. Keep in mind that this is an AMD CPU system, not Intel.

Do you have room for something more vertical, such as Coolermaster Hyper 212 Plus CPU Cooler?

I don't think you've said it, what is your CPU and current RAM?

Not that you want to boost it, but I found a good article to help understand how it all works; http://www.overclockers.com/forums/showt...p?t=596023

Motherboard is Asus M4A79T Deluxe. CPU is Phenom II 720 BE. But as it happens I changed the memory this afternoon. Old memory was OCZ3RPR16992G. New memory is Mushkin 997000. Newegg dropped the price of the Mushkin the day after I bought it. Why?

I've known about the overclockers article for some while. It is one of my bookmarks. I read it ever few months whether I need it or not, but it never seems to make much sense to me, particularly the part about reduced NB timings. I read somewhere that AMD originally designed the CPU NB (that is the L3 cache and memory controller) to run *faster* not slower than the CPU itself, but that they couldn't make it happen.


The documents I found most useful this time around were:

http://sites.amd.com/us/Documents/AMD_Dr..._Guide.pdf

http://en.wikipedia.org/wiki/DDR3_SDRAM


The Mushkin DIMM's sit about an inch lower than the OCZ ones, but they still would not go in bank 1 because of the cooler (Zalman CNPS9700 NT). Interestingly the AMD document, under the section Memory Performance tuning – AM3 / DDR3, says "The DIMM slots furthest away from the CPU socket should be equipped first (usually marked as DIMM slot 2&3 or A2&B2)." That is where my memory is!

This is contrary advice to what the Asus motherboard manual says. Very confusing.

In any event the Mushkin seems to work at its rated 1600 7-8-7-24 timings. No crashes yet in my stress test. (Though the dailies don't reset till 4:00am.) I never could get the OCZ to work at its rated timings at all.

The biggest problem installing the Mushkin was because my floor is uneven. In putting the computer back next to the other computers, I have to lift the left rear caster to get it up on a pile of cardboard without crushing any cables.

Unfortunately I could not leave the system well enough alone. After I satisfied myself by running diagnostics that everything was stable I tried putting the NB up one more notch, from 2600 MHz to 2800 MHz. This was a mistake. No POST, no nothing. As I get older it becomes harder and harder to find the CMOS reset jumper. The NB is now back down to 2600, but as I was fiddling with the pile of cardboard I caught my hair between the side of the computer and the desk. As William Blake wrote, "You never know what is enough unless you know what is more than enough."

Once when I was much younger (in my twenties) and computers were much larger, I caught my hair around a fan. A merry laugh was had by all. I was stuck for quite a good long while.

Before I ordered the memory I was doing some measurements. With two instances of WoW and a bunch of browser windows open I was running up to 91% memory utilization. I also noticed that when I got a stutter it was associated with a massive spike in page faults. I am enough of a scientist to know that association does not prove causality but it certainly seems suspicious. I still have yet to move the pagefile to the SSD.

The little tweaks have not gotten me up to a consistent 60 frames per second, but I am closer. Now when I spin around in Ramkahen I don't go much below 40 FPS. So that is progress.