8meg cache 'cuda

jhh · Post by **jhh** » Sun Feb 02, 2003 2:21 pm

are these normal? being a french speaker I sometimes check out .fr shopping sites, and found a 120gig model for 215euro.

I thought the 'cuda all had 2meg caches?

Gekkani · Post by **Gekkani** » Sun Feb 02, 2003 2:23 pm

There are 2 versions of cuda V. 2mb and 8mb ... ATA and SATA

jhh · Post by **jhh** » Sun Feb 02, 2003 2:42 pm

nope, it certainly says ATA, see this link...

http://www.ldlc.fr/fiche/PB00016194.html

FYI 8Mo = 8Meg

jamoore9 · Post by **jamoore9** » Sun Feb 02, 2003 3:08 pm

Per Seagate's website, the model Barracuda for sale by that French retailer DOES have an 8MB cache:

http://www.seagate.com/cda/products/dis ... 72,00.html

Don't know where it is for sale, though.

jhh · Post by **jhh** » Sun Feb 02, 2003 3:35 pm

quick google search seems to sugest ldlc's the only place on the web that's doing them atm.

interesting but a bit out of my price range.

cjp · Post by **cjp** » Sun Feb 02, 2003 4:37 pm

www.komplett.co.uk sell all three varities of 120gig Seagate Barracuda V.

But I'm not sure it is worth the extra money for the 8meg cache.

jhh · Post by **jhh** » Sun Feb 02, 2003 6:38 pm

yes, £20 does seem a lot for a measly 6megs extra ram, not like it even has to be high spec memory in a device with such a tight bottleneck.

there's proberbly some technical reson behind it, maybe diminishing returns, but I've never really understood why hard drives have so little memory - I'd like to see one with a whole stack of chips acting like a little rocket-drive for the most used files.

GamingGod · Post by **GamingGod** » Sun Feb 02, 2003 7:08 pm

yea a harddrive with 256, or even 512 of cache would rock, id like to see how one would perform, and if it was signicantly faster i would pay close to twice as much for one.

jhh · Post by **jhh** » Mon Feb 03, 2003 5:01 am

there's the argument that a bigger a cach is the slower it is to access, and so the less difference there is between the cache and the thing you're caching, but in reality I think it'd be near impossible for a cache using ram to be as slow as disk access.

I suppose there's no reson why someone couldn't write an OS that'd use ~10% of system ram to cache the HDDs

cjp · Post by **cjp** » Mon Feb 03, 2003 11:43 am

Linux will use most of the otherwise free main memory as disk cache. I have 512MB of main memory of which 144MB is currently needed and 358MB is being used as buffers/cache. The bulk of which is disk cache. 4MB is really free and the rest was used/reserved by the kernel at boot time.

So for a drive's onboard cache to have any significant effect it would have to primarily do some kind of speculative caching.

jhh · Post by **jhh** » Mon Feb 03, 2003 12:21 pm

ooops - double post

jhh · Post by **jhh** » Mon Feb 03, 2003 12:22 pm

wow so if you have linux and a pile of redundant ram then that's pretty much halfway to being a rocetdrive right there (for recently accessed stuff anyway). Only faster becasue it doesn't have to go through the PCI bus - wow!

in fact in linux a large cache must just slow things down since system ram's far faster than anything coming down an IDE interface

Damit now why can't windows do that? I'd like to bet that of my 512megs almost all atm is doing nothing at all.

pingu666 · Post by **pingu666** » Thu Feb 06, 2003 5:01 pm

i did think makin a pass thru box with ram in would be possible
moniters what files are being sent, caches them in its bank of ram, intercepts requests etc
might be a tad costly tho

jhh · Post by **jhh** » Thu Feb 06, 2003 5:23 pm

well it'd only have to use low-spec pc133 ram that noone wants anymore and would only need a very simple and slow controler, and you could keep it when you upgrade your drive etc.

problem is it'd have to flush itself when pc is turned off, if there's a lot cached to write that'd proberbly take longer than the OS shutsdown and files would be lost. nice idea tho.