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To: jeffc
Found this:

SSD vs. SATA RAID: A performance benchmark

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The random seeks were about 6,200/second for ext3 and 3,800/second for XFS on the SSD. To put this into perspective, the graph shown below contains the seek performance for the SSD, a single 750GB SATA drive, and six 750GB SATA drives in RAID-6. Notice that having six hard disks does improve seek performance noticeably over a single hard disk, but the single SSD still dominates the graph. This advantage in seek time explains why systems equipped with a SSD drive can boot significantly faster than those without. Booting a machine or loading a complex application normally calls for thousands of files to be read, and these are normally scattered over a disk platter, causing many seeks. Because the SSD has such an advantage in seek time, it can show with an overall improvement measured in seconds to load a very large application. Bonnie seeks

The final graph shows the block read, write and rewrite performance of the SSD against a single 750GB disk and a RAID-6 of six 750GB SATA drives. There isn't a great deal of difference between the block transfer performance of a single 750GB SATA drive and the SSD. The RAID-6 of 750GB conventional hard drives is significantly faster across the board. Bonnie vs RAID block IO

The point of the previous comparison on block transfer is to show the gap between the block IO performance you would get if you spent the same money on conventional hard drives instead of the SSD. The SSD has a dominating advantage in seek time, yet its overall capacity is a slight fraction of what you can get by buying conventional hard drives, and hard drives in RAID dominate the SSD in terms of block transfer speeds.

13 posted on 05/04/2009 10:47:41 AM PDT by Ernest_at_the_Beach (Support Geert Wilders)
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To: Ernest_at_the_Beach
Thanks. I was assuming (correctly, I think) that SSD seek-time would help it beat anything the SDD (Spinning Disk Drive) would have over and SSD.
With faster seek-times couldn't an SSD use smaller cache and pre-fetch and smaller block transfer sizes, making it even faster?
This would mean you wouldn't need as big a bus and could speed up transfer times even more, right? Or are bits leaking out of my head onto the floor (wouldn't be the first time, LOL!)?
18 posted on 05/04/2009 11:20:14 AM PDT by jeffc (They're coming to take me away! Ha-ha, hey-hey, ho-ho!)
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