sub mesa :
http://images.anandtech.com/graphs/intelx25mg2perfpreview_072209165207/19508.png
Still alot better than the best consumer class HDD, the Velociraptor. So i don't understand your argument in writing.
Modern SSDs like Intel do not do 2-phase writes but they use free space so don't have to erase the block because its already erased. This is also the reason they require free space or they will be very slow when writing. For example if you filled your SSD to 100% then removed files but without TRIM support the SSD would not know that, and can't remap random writes to free flash blocks.
Maybe if you look at JMicron (JMF-602 controller) SSDs, they should only be used in Read-many-write-few situations, for example light desktop pcs for web browsing would be sufficient, as read latency still is a key advantage to HDDs even on cheap SSDs.
The adjusting of the sectorsize story is a way to involve all disk members in one I/O transaction. This very much hurts performance on SSDs and didn't gave meaningful performance advantages on HDDs as well. Its best if an I/O request can be handled by exactly one disk member, so that other disk members can be loaded with different I/O requests at the same time, and process them in parallel. If you don't do this, you may have proper sequential speeds, as they are buffered anyway, but you won't have an increase in IOps performance which is key.
An intel SSD can do already 35.000 random read IOps. With RAID0 you can lift that to 100.000+ so enterprise-level performance is now in the reach of casual consumers. That's pretty remarkable honestly. HDDs totally get nuked by this kind of (low-level) performance:
http://images.anandtech.com/graphs/intelx25mg2perfpreview_072209165207/19506.png
Hm, I made 2 'arguments' I suppose. Neither was a focused slam on SSD, and my goal was to address the issue of SSD in a RAID 0 for backup purposes.
Basically the first one was that SSDs are currently, great for certain IO profile(s), but show contention in others - however this storage platform is evolving constantly. You have shown that in your reply. Thanks for the updated article to show that there is new tech being released that is addressing issues with the some specific write profiles (as even stated where these benchmarks are posted). Looks like random writes on the new gen of SSD is great, I would still like to see these synthetically bench-marked against 15k SAS for all profiles, as that is technically as consumer available as SSD, and interfaces are becoming more apparent in consumer motherboards, etc - more or less as that is what it is been traditionally pit against (and the raptors 2nd).
Though I have no doubt that SSD is a potential all purpose future of storage for consumer, and has its uses now.
The other was the general use of RAID and backup, and general drive practicality. Adjusting sectorsize story? RAID 0 stripe width and tweaking is a constant debate - but the fact remains it depends on what IO profile you are seeking. Generally speaking, RAID 0 stripe is going to end up being a factor of sector for a great deal of stripe optimization (i.e. if you are using clusters to base your stripe width) - for parallel process, contiguous IO to disk, and low seek - which is the desire of striping. Not attempting to create a blanket statement because of course you should choose the correct stripe for your expected IO profiles (and whether or not you can optimize within those boundaries), and results are going to depend on controller, disk...and adjust from there. Was not attempting to state a specific for those above reasons. As for the SSD stuff I left that open for someone else to conclude - as I'm not an up to the minute expert when it comes to SSDs, but have some experience with the, I suppose now, older tech.
Honestly, I think RAID 0 gets used a bit too much, not saying it doesn't have its place (esp if that data is more or less volatile - highly repurposeable consumer and some server OS drives, etc) especially when you don't see double the performance gains across the board in real world (as its generally marketed), and can achieve great performance results with actual RAID volumes if you toss in your coin for decent HW, and wish to keep your data around. Again it has its place, IO profiles, and if you implement for those properly, more power to you.
So the second point - are SSDs in RAID 0 good for backup? My personal opinion was most likely not at this point in time and not on RAID 0. Generally, backup can be treated as tier 2 storage, mainly involves sequential sweeping writes, and is a high availability operation. I did, however, want to give some alternative options...
Not going to stop anyone from flaming away...most likley departing from the thread, hope I was of some benefit.
Thats it for my $.02 again, and apologies for the ramble!