Topic: Need raid controller (Read 1484 times)
I know no trim with raid but i got them brand new so i wont need to worry about performance loss for a long time. I can always disable the raid and wipe them. Looking for a good raid controller cause i would like to stabilize my performance and reduce cpu load. 1000 minimum would be nice. I will look in to the 1880i. Anybody know a few more model numbers?
A good modern SSD should have a decent garbage collection algorithm built into the firmware, but not all of them have one. If you are going to use RAID, get drives that have hardware GC.
The issue is the SSD has no idea is a file has been deleted. That is because when you delete a file the OS doesn't even notify the drive. The OS simply records the delete in the file system. With magnetic disks this is a non-issue because there is no overhead/cost in writing over existing data. As a side note this is how utilities can "undelete" files. It is also why if you have a drive failure you should boot from another disk and only read from the corrupt/damaged drive.
Since the SSD doesn't know the file is deleted it can't do the "expensive" erase operation until the OS writes new data to the block. The presence of good GC doesn't change the fact that without TRIM the SSD simply doesn't know the OS "thinks" the page is empty.
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The TRIM command is designed to enable the operating system to notify the SSD of which pages of data are now invalid due to erases by the user or operating system itself. During a delete operation the OS will not only mark the sectors as free for new data, but it will also send a TRIM command to the SSD with the associated LBAs to be marked as no longer valid. After that point the SSD knows not to relocate the data from those LBAs during garbage collection. This will result in fewer writes to the flash, reducing write amplification and increasing drive life.
A good modern SSD should have a decent garbage collection algorithm built into the firmware, but not all of them have one. If you are going to use RAID, get drives that have hardware GC.
Where hardware RAID cards really shine is with high queue depth. Unless this is going into a database server box or something that is going to sustain a high level of concurrent user activity you aren't gaining much. Actually the loss of TRIM will mean in the long run degradation of performance.
You are going to READ mostly, so just run your onboard RAID in RAID 0 and call it a day.
For the price difference, you will barely notice a difference unless you are doing alot of simultaneous writes to the drives.
I run 3x Intel X25-V 40GB SSD's in RAID 0 on ICH10R and get a steady 700MB/s throughput on SATA II for Reads, as it's simply my boot/program volume.
My rig takes longer to turn on and post than it does to boot and that's all I need...
For the price difference, you will barely notice a difference unless you are doing alot of simultaneous writes to the drives.
I run 3x Intel X25-V 40GB SSD's in RAID 0 on ICH10R and get a steady 700MB/s throughput on SATA II for Reads, as it's simply my boot/program volume.
My rig takes longer to turn on and post than it does to boot and that's all I need...
Keep in mind that putting SSDs in RAID does not provide for TRIM support.
I'veused Highpoint and was underwhelmed, especially by their support.
Areca is who I swear by now.
Get an 1880i, you won't be disappointed.
Areca is who I swear by now.
Get an 1880i, you won't be disappointed.
You could try the Highpoint Rocket series. I have one (not for raid) and it works great for my corsair force SSD.
Just got a pair of OCZ agility 3 from amazon for $55 each. Can anybody recommend a good hardware raid card that supports SATA 3 and SSD?
http://www.amazon.com/Agility-2-5-Inch-Midrange-Performance-AGT3-25SAT3-60G/dp/B004Z0S6RU/ref=sr_1_2?ie=UTF8&qid=1337329768&sr=8-2
http://www.amazon.com/Agility-2-5-Inch-Midrange-Performance-AGT3-25SAT3-60G/dp/B004Z0S6RU/ref=sr_1_2?ie=UTF8&qid=1337329768&sr=8-2
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