On Sun, 2011-05-08 at 13:27 +0300, shimi wrote: > > > b.t.w. IIRC when a cell dies, it does so "gracefully"; I.e. no data is > lost, and there are spare blocks for that case... and even when > they're all full, you just get to the point that you still have your > data read-only. I vaguely remember I read that somewhere... and if > it's indeed like that, this is still way better than a regular hard > drive - those tend to usually take all your data with them, and are > much more sensitive to many things (shock - physical/electric, heat, > etc...)
While its very unlikely that you'll ever come close to reaching the (more-or-less-theoretical) per-cell write limit, SSD's do have their share of major issues that should be taken into account: 1. Bricking: As a general rule, SSD's are -far- more vulnerable to data corruption and data loss issues and the reason for this is rather simple: Compared to spinning HDD's, SSD's have highly complex firmware that uses complex write-leveling algorithms and, in some cases, complex compression schemes. (SandForce SF-1xxx, SF-2xxx controllers) As a result, any corner bug in the SSD's firmware will usually brick your SSD, leaving you with nothing. Far worse, while we (as an industry) have extensive of experience in yanking data out of a damaged spinning HDD's, there's far less collective experience in dealing with bricked SDD's. 2. Experience: We literally have decades of experience with dealing with spinning HDD's. Give me a RAID with 1,000 drives and I can predict how many drives will die each month, each year. On the other hand, we simply do not have sufficient experience in dealing with high-end SSD's to draw the predict the same when it comes to SSD's. 3. Performance: TRIM, file-system optimization, dealing with drives running at >90% full capacity, etc. Getting the most out of an SSD's requires careful planning. Let me be clear: I do not doubt that SSD's will slowly replace spinning drives in 90% of all the use cases. I am saying that I'd consider twice before using SDD's in mission critical environment on in places with inadequate backup strategy. - Gilboa _______________________________________________ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il