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no more xp, no more vista. . .

well with the exception of Kris' netbook. . .

the whole house is now running Windows 7 or Server 2008

I *REALLY* love windows 7

AND

I was able to upgrade my Build 7100 RC1 Ultimate Machines to Build 7600 Professional without any issues.

The gaming rig is humming along nicely, the slowest item in the windows score is the 10K RPM Western Digital Raptor. . .

um, guess I won't be increasing the speed by modifying *THAT*

Comments

deprivation
Aug. 19th, 2009 05:49 pm (UTC)
i wasn't suggesting RAID 0 - just noting that it wouldn't speed up writes any, even if it were safe :)

RAID 1 is mirroring - but there is a significant speed difference:

o writes can be asynchronous, so no requirement to write to all drives at the same time, one write and one write scheduled for later

o reads happen in parallel - reads can happen from all devices simultaneously, typically the RAID controller (software or hardware) will optimize reads, at worst case reading data from the device whose read head is closest, limiting seek time


RAID 5, on the other hand, uses parity computations on writes. the benefit of RAID 5 is only having to sacrifice one device for redundancy. give 3 devices, you only lose 1/3 of the combined storage space for the benefit of redundancy.

unfortunately, with RAID 5, all writes must happen on all devices to guarantee parity, and all writes require an expensive parity computation before they can happen. this means significantly slower write times.

as an aside, for home, where speed is unimportant, but capacity and redundancy are, i use RAID 5. for any servers deployed, i use either RAID 1 or RAID 1+0 depending on the requirement: 1 for webservers, 1+0 for database.

on a heavily loaded machine, i've seen write times move from seconds to milliseconds moving from RAID 5 to RAID 1+0, on heavily loaded Oracle RAC clusters.