New Intel 320 - why are writes so slow?

[dsiomtw]

Just got 2 Intel 320s and currently have them in a RAID 1 setup.

Long story short ... why are my reads so much faster than advertised and my writes less than half of what they advertise?

Do SSDs behave differently in a RAID (or RAID 1 for that matter)? With standard HDDs I'd usually see about a 10% gain in reads and a 10% loss in writes, whereas these are getting significantly faster reads and significantly slower writes.

The partition is aligned properly, although I aligned it after the fact. I didn't get it right the first time around, and ended up using the Paragon Alignment Tool. The offset is 2048 and AS SSD confirms it is "OK" in the upper left corner.

I've also done all of the standard "tweaks" I've read about...

 

[sminlal]

I'm not familiar with the Paragon Alignment tool - does it literally rewrite all of the blocks in the partition when it realigns it? If so, that might have ended up screwing up the garbage collection algorithm in the drive by causing the drive to believe that all of the blocks are in use.

 

[dsiomtw]

I can't say for sure exactly what it does.

I started from scratch and I'm still having the same problem.

I destroyed the RAID, updated the firmware on both drives, updated the Intel RST driver to the latest version, updated the chipset drivers to the latest version, did a secure erase on both, then created new partitions on both that are properly aligned with a 1024 offset from the start.

My write speeds are a tiny bit faster but not even hitting 100. My old raptors were faster and wrote at about 125!

Anyone have any ideas?

 

[dsiomtw]

Upon further research, apparently this is about the norm for the Intel 320s, at least the 80GB versions I have. I now have them in a RAID0 with 128k stripe and I'm seeing about 175 writes and 525 sequential reads. Still a big improvement over my previous raptors I guess ...

 

[sminlal]

Upon further research, apparently this is about the norm for the Intel 320s, at least the 80GB versions I have.

SSDs in the same model category which use the same controller often come in several sizes, and the larger sizes generally perform better because they use more flash chips and read or write to them in parallel.

 

[dsiomtw]

You're right. Guess I should have done more research before buying. The 120GB Intel writes almost twice as fast as the 80GB. Doh!