Yesterday I was unzipping about 300MB of Javadocs to my HDD. I noted that it unzipped at about 30-40MB/sec for the first two seconds, then dropped down to 4-5MB/sec. Out of interest I then unzipped the same files to my SSD. It unzipped at a constant 30-40MB/sec. (probably CPU limited)
What I was seeing was probably the effect of write caching to the drive's 64MB cache. If I pause the unzipping I still hear my HDD chattering away - but then if I resume unzipping after the chattering stops, it again unzips at about 30-40MB/sec (for 2 seconds), confirming my suspicions.
I like this caching. Lots of gamers would too. Every once and a while coders do silly things like dump 120MB debug files to the HDD in a single frame, causing massive lag. A few TF2 updates resulted in 1-3 second jolts for laptop users, but on my 64MB cache drive the jolts were only a fraction of a second. I think even larger caches would eliminate a lot of the stutters that HDD users face when gaming, and would have a very positive effect on how fast a drive feels.
A while back I experimented with RAM caching, using trials of products like SuperCache and FancyCache. Unfortunately I had to discontinue their use - RAM caching plays havoc if you suffer a BSOD... And that is where drive-level caching matters. If my OS crashes, then my HDD still happily chatters away, completing its tasks.
I suppose my question is, does WD plan to release any drives with large amounts of cache? I mean 512MB+; If it only increases the price by $20-60, people will buy it. I feel there's a market here... comprised of gamers. (and perhaps power users that own UPS's)
Obviously optimal use of larger amounts of cache is not as easy as flipping a figurative switch. But if WD was able to incorporate similar write-combining logic to what FancyCache and SuperCache have implemented, it would vastly speed up many tasks. Some tasks involve writing to the same location multiple times, or writing many smaller chunks serially - these could all be completed instantly (as far as the OS is concerned) and then combined into larger sequential writes to the platter surface. Current drives already do this to some degree, but with a much larger cache it could be taken much further, and benefit quite a few more advanced tasks. It's got to have a very positive effect on performance.
It'd also be nice if such a drive prioritized reads over writes, as that would virtually eliminate stutters in games (and reduce usefulness in enterprise scenarios Can't cut in on that market, can we? ) Going back to that poorly coded game and 120MB debug file - the drive absorbs it and continues on, and thanks to read prioritization it does not get jammed up if the game requires reading a texture or model the very next frame. Who needs an SSD when you can get a 2TB drive with very few of a regular HDD's weaknesses?
More cache could be very fun for us power users... depending on what the drive's firmware is coded to do. I wonder if Western Digital has considered boot preloading like the Momentus XT has? If a hard drive recorded which blocks are needed during booting, it could preload many of them to that nice big 512MB cache before your OS even starts loading. (I'm thinking of Desktops here, with long POST times - often 25-35 seconds on high end gamer boards... that's at least a 10 second headstart after the drive(s) initialize.) An HDD with SSD-speed boots would certainly make headlines, and gamers wouldn't think anything about dropping an extra $60+ on that.
Anyway, thank you for your time. I hope someone reads this and considers it.