we are looking into 3 drives
Seagate Constellation ES.3 ST1000NM0033 1TB 7200 RPM 128MB Cache
Western Digital WD VelociRaptor WD1000DHTZ 1TB 10000 RPM 64MB Cache
Seagate Hybrid Drives ST1000LM014 1TB MLC/8GB 64MB Cache - HYBRID SSD
QUESTIONS IS (please answer it in order if possible, i would really appreciate it)
ASSUMING we do not use it in RAID environment just single drive
1) Which drive will perform better if we do Virtualization (which we are using KVM Virtualization on Linux server)
2) Since each drive have different role, one has higher RPM and one have higher cache and one have lower RPM (hybrid ssd but it has SSD 8GB on it) - which one will reduce I/O on the server/
3) if we used raid controller, is that right the cache on the drive itself will be disable and therefore the raid controller cache will come into the play - what i mean is, if the raid controller have 128MB cache and the bare drive have only 64MB Cache, as soon as we use raid controller that have 128MB cache, the cache for the drive will be 128MB CACHE?
4) Which drive from those 3 will be the best for read, write and reduce I/O under extreme condition
PS: I dont put SSD into the picture because of the pricing, therefore i need to know how can we create similar to SSD performance using above drives?