SSD writes are about half what they should be?

[Mars999]

I am not sure why, but all my SSD drives are about half on their write speeds as I see on benchmarks?

Any ideas?

Thanks!

 

[VirtualLarry]

Are your partitions aligned?

 

[Mars999]

Should be I formatted them in Win7? And my reads are about where they should be? Do you have any way I can check the alignments?

Thanks

 

[VirtualLarry]

http://forums.anandtech.com/showthread.php?t=2215973

Did you just format them in Win7? You actually have to partition them with Win7 for them to be aligned, not just formatted.

 

[bryanW1995]

How large are the ssd's? Most manufacturers show significantly faster sequential read/write speeds up to the 256-300 gb range. A 128 gb or smaller drive will be a lot slower.

 

[Mars999]

How large are the ssd's? Most manufacturers show significantly faster sequential read/write speeds up to the 256-300 gb range. A 128 gb or smaller drive will be a lot slower.

I have a Vertex 3 240GB and a Mushkin 120GB Chronos Deluxe and both are reading slower than others on writes... Reads look fine.


Asus P8P67 Deluxe MB latest BIOS

and they are both on intels 6GB controller and I installed the latest intel RST driver and used MS driver no difference to talk about

 

[Mars999]

here is what MS diskpart says



Uploaded with ImageShack.us

looks like they are aligned to 1024

 

[Engineer]

Do you have the write cache enabled through Windows?

Device Manager > Disk Drives > drive in question > Policies > Enable drive write caching.

 

[Mars999]

Do you have the write cache enabled through Windows?

Device Manager > Disk Drives > drive in question > Policies > Enable drive write caching.

Yep

On all my drives

 

[Mars999]

Found it...

The benchmarks are quite different, ATTO uses fully compressible test data and CDM uses fully incompressible test data to determine the speeds.
A Sandforce drive gains some of it's speed by compressing data on the fly.

 

[bryanW1995]

According to Anand, a sandforce drive's real world sequential read/write speed is typically about 1/2 btwn the compressible and incompressible speeds fwiw.

 

[groberts101]

I'd say closer to 70% towards easily compressed data. Unless you do a lot of HD vid/music/gfx editing or constantly stream HD vids to your SSD. So, it's usage dependant of course.

If 50% was the real speed?.. then these drives would not compare as well as they do with all the other drives not relying on compression and showing much stronger incompressible write speeds.

People just get too caught up on the SF compression weakenesses and forget to look at the strengths they use to beat up on other seemingly more capable controllers.

 

[bryanW1995]

No, people get caught up with the beta firmware and unreliability of sand force drives. Performance-wise they are fantastic.

 

[groberts101]

Probably true when boiled down enough. Although.. I would point out that all mfgrs who are first to market with a new controller.. could also be called out for using "beta-firmware" to some degree. Ever notice how they change/revise them so quickly after release?

Same could be said about bios and drivers for newer platforms as well. In a sense.. we're all beta-testers in some form or another. Some brands just push the envelope a bit further than others, is all.