On 200802290116, Michelle Konzack wrote: > Am 2008-02-27 21:10:03, schrieb Anders Breindahl: > > I.e., other factors omitted, you could continuously push data onto such > > a 4GB 10^6 high-endurance drive at 50% levelling at 10MB/s for > > > > 4*10^9/10^7*10^6 * 0.5 / (3600*24*365.2524) = 6.3 years [ heavy snipping ] > > Why would this not suffice for server applications? Especially > > considering the good random access times of SSDs, and the fact that we > > will use these drives in RAIDs anyway? > > I have killed a new bueyd 4 GByte "SanDisk Ultra II" (27 Euro in Germany) > in less then one month writing a copy of my ~/Maildir to it and the read > it ober "courier-imap"... Those are flash memory cards, and have a very low-level interface -- i2c, IIRC. Those can't be assumed to do wear levelling on their own, and if you just used your standard filesystem on them, that is sure to waste the cells fast. > A normal 2"5 HDD (PATA) was gone in around 10 Month... so why should a > SSD be longer live, if it can not beat a HDD physicaly. See the Wikipedia article; there's pros and cons for both conventional disks and SSD's. (And apart from the wearing of SSD's, they're all in SSD's favour, I might add). When wear levelling gains momentum, Flash-based memory looks very mature for even server usage. And, not to forget: Even cheap SSD's compete with high-end harddrives when it comes to linear transfer rate ([0] says 100MB/s read, 80MB/s write), and have <1ms access latency. Couple these, and you get impressive random read/write speeds, which harddrives have a hard time achieving. [0] http://www.samsung.com/global/business/semiconductor/products/flash/Products_FlashSSD.html Regards, skrewz.
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