I want to build let's name it a lowcost Ra*san which would host for our social site the images (many millions) we have 5 sizes of every photo with 3 KB, 7 KB, 15 KB, 25 KB and 80 KB per Image.

My idea is to build a Server with 24x consumer 240 GB SSD's in Raid 6 which will give me some 5 TB Disk space for the photo storage. To have HA I can add a 2nd one and use drdb.

I'm looking to get above 150'000 IOPS (4K Random reads).

As we mostly have read access only and rarely delete photos i think to go with consumer MLC SSD. I read many endurance reviews and don't see there a problem as long we don't rewrite the cells.

What you think about my idea? - I'm not sure between Raid 6 or Raid 10 (more IOPS, cost SSD). - Is ext4 OK for the filesystem - Would you use 1 or 2 Raid controller, with Extender Backplane

If anyone has realized something similar i would be happy to get Real World numbers.

UPDATE

I have buy 12 (plus some spare) OCZ Talos 480GB SAS SSD Drive's they will be placed in a 12-bay DAS and attached to a PERC H800 (1GB NV Cache, manufactured by LSI with fastpath) Controller, I plan to setup Raid 50 with ext4. If someone is wondering about some benchmarks let me know what you would like to see.