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Kevin OBrien

Samsung SSD 830 RAID Review Discussion

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thx. like the layout & the drives u picked for comparison.

can u please tell me why u picked the 128 sector size? stil learning a lot of this stuff and sincve im going to be seeting up a raid 0 setup on my iwfes comp with 2 wd re4's a litle info would be helpful.

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128K stripe worked out best when it came to giving the best ground in our traces. It really depends on your workload though. Let me try to dig out an old forum thread where we covered stripe size versus real-world scenarios.

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128K stripe worked out best when it came to giving the best ground in our traces. It really depends on your workload though. Let me try to dig out an old forum thread where we covered stripe size versus real-world scenarios.

thx! would appreciate that very much

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While I find the data interesting and of worth to see what a RAID0 looks like on this product. I cannot see why or how you can justify comparing RAID'd drives with Single drives and call it a valid comparison. Shouldn't the comparison data be RAID'd drives as well to add any value or validity to the data you gathered. Otherwise the data on comparison is just muddying the review

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While I find the data interesting and of worth to see what a RAID0 looks like on this product. I cannot see why or how you can justify comparing RAID'd drives with Single drives and call it a valid comparison. Shouldn't the comparison data be RAID'd drives as well to add any value or validity to the data you gathered. Otherwise the data on comparison is just muddying the review

Generally speaking not many manufacturers send more than one drive in for review, making full comparisons between RAID options sparse in the same performance category. For that reason we will generally plot RAID results in with the same batch of drives we originally used when comparing that product, primarily to show how much performance changes compared to the original drive.

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128K stripe worked out best when it came to giving the best ground in our traces. It really depends on your workload though. Let me try to dig out an old forum thread where we covered stripe size versus real-world scenarios.

i looked around a little bit & couldnt find it. if u give me general clue i will locate it. if it isnt in your archives that is...:)

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Would love to see steady state results for Samsung 830 single-drive and RAID. Would be very interesting as I heard garbage collection is quite slow in this model.

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Going to be gathering those results later this week when we are back in the office after CES. Around that time I will probably knock out whatever other controller/NAND combo that is also laying around.

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"Slow" garbage collection really means that garbage collection is "delayed" until the drive is idle. Garbage collection is used to clean up the drive in order to maintain it at peak performance. By delaying garbage collection you can increase performance *right now* but if you leave it for too long then you get a build up of garbage and then the performance turns to rubbish, excuse the pun. The SR steady state tests illustrate this concept. (note: for a client/consumer drive this doesn't really matter unless you use your SSD for long sustained periods).

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"Slow" garbage collection really means that garbage collection is "delayed" until the drive is idle. Garbage collection is used to clean up the drive in order to maintain it at peak performance. By delaying garbage collection you can increase performance *right now* but if you leave it for too long then you get a build up of garbage and then the performance turns to rubbish, excuse the pun. The SR steady state tests illustrate this concept. (note: for a client/consumer drive this doesn't really matter unless you use your SSD for long sustained periods).

thx!!

for me(average use) it wont be a 'problem'

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While I read for only 2 pages into the threat on prior research on stripe size, I wonder if you can include some tests in the future on RAID0 SSDs. From my understanding of RAID0, the stripe size is usually kept larger on mechanical drives as it help keep the costs of seeks low when you have 2 spindles to precess incoming IO requests. When SSDs have no real penalty for random access patterns, wouldn't a stripe size on the order of the SATA interface be faster? ie, use a 4k stride.

I currently don't have a second SSD to test this against, so please take this into consideration the next time you have 2 identical drives to test against!

Cheers,

Q

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Well the way most RAID systems are designed, you only have a set number of stripe options (usually 64KB is smallest) to choose from. We have Crucial m4 RAID0 review upcoming that we can play around with the stripe sizes once the review is complete to see how things change in different areas.

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Well the way most RAID systems are designed, you only have a set number of stripe options (usually 64KB is smallest) to choose from. We have Crucial m4 RAID0 review upcoming that we can play around with the stripe sizes once the review is complete to see how things change in different areas.

Interested to find out how you handled the lack of TRIM support when using these drives in a RAID configuration. Over time most reviews I have seen shows serious performance degradation without TRIM.

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