Slow disk performance on new setup

Joined
Mar 20, 2013
Messages
24
Hi - I am very "green" when it comes to RAID and SSD's.... recently put together a new machine which runs Intel 5500 with a dual Intel X5660 Xeons. I have also put in a RAID card M1015 and flashed it to LSI 9211 IR mode.

I hooked up a new Samsung 840 Pro 128GB SSD (MZ-7PD128BW) and built a virtual disk consisting of this single drive.

I have installed Windows 8 (to do some bench marking) and quickly have come to realize I am looking at pretty lousy Read/Write speeds - I am using CrystalDiskMark latest version 3.03 and this is telling me I am getting sequential read speed 155 MB/s and write speed 133.7 MB/s. Now I know that this setup is cable of more.

Definitely still learning the ropes when it comes to it but I suspect I have configured the virtual disk incorrectly.

Running MegaRAID Storage Manager I see that

CacheCase SSD caching is disabled - not sure if this should be or not....
Drive Speed is 6.0 Gbps -- good
Disk cache policy is disabled
read policy - no read ahead
IO policy - direct io

Any body got any advice as to how to improve things ?
 
Running MegaRAID Storage Manager I see that

CacheCase SSD caching is disabled - This is for when you are using an SSD as a cache for a HDD array - no point in enabling.
Drive Speed is 6.0 Gbps -- good
Disk cache policy is disabled - if your RAID card has RAM, definitely enable this. Depending on the card you may want to enable this even if your RAID card doesn't have RAM. If it is disabled, it may not let the OS do any kind of cacheing for your drive.
read policy - no read ahead - enable this.
IO policy - direct io

As it is, there is almost no point in using a RAID card with a single SSD unless you have one with RAM cache.
 
Thanks for the replies. Yes I know bit lame a single disk - whole project is still a bit of work in progress....

I enabled the disk cache policy and reads are looking better:

Disk cache policy OFF:
4rz3.jpg

Disk cache policy ON:
3qmc.jpg


As for writes is this degradation in performance explainable by turning disk cache policy on ?


Regarding the read ahead there doesn't appear to be any other option than "No Read Ahead".

Or am I missing something?

I plan to buy a second drive soon and setup a RAID 10 array.
 
yes RAID 0 would I expect improve read performance.

Some what worried though about how to get the write figure improved. I think I read that Raid 0 doesn't improve write speeds... I could well be wrong again though

1dan.jpg


:(
 
RAID0 with SSDs does not improve performance that much with real world desktop applications however it will help in specific applications that read or write files in very large chunks or on systems with high queue depths like servers.


Your benchmark numbers are all bad. I would try using the intel ports instead.
 
Why is the partition your doing the tests on only 47gb, It's a 128gb SSD right?

Does the M1015 pass Trim in Raid? Can you set it up in JBOD?
 
Some what worried though about how to get the write figure improved. I think I read that Raid 0 doesn't improve write speeds... I could well be wrong again though

Of course it does.

But here's the deal, you're trying to make a silk purse out of a cow's ear......

1. The smaller the SSD the slower it is and yours is small.
2. The LSI 9211 is an entry level card and won't ever give decent RAID0 performance.
3. Forget the card, hook your SSD to the Intel ports and when/if you get another SSD use Intel's RAID.

4. Use Google to find articles on RAID configurations (there's a zillon of 'um) and get a little education.

Good Luck!
 
i bought some special rounded sata cables and i was getting very low score on as ssd. i did lots of things and nothing. the only thing left was to try the "ordinary" cables that came with my motherboard. my score jumped to more than 1000 points in as ssd benchmark. go figure.
 
i bought some special rounded sata cables and i was getting very low score on as ssd. i did lots of things and nothing. the only thing left was to try the "ordinary" cables that came with my motherboard. my score jumped to more than 1000 points in as ssd benchmark. go figure.

LOL!
 
Back
Top