The SSD Improv | Hacker News Reader

The SSD Improv

anandtech.com

40 pointspieter17 comments

Full print-view article: http://anandtech.com/printarticle.aspx?i=3667

Another well written and researched piece of tech journalism from Anand Lal Shimpi. Good to know the strengths and weaknesses of the Indilinx products. Considering how hard it is to get your hands on an 80G X25-M, I might have to start looking at OCZ or SuperTalent products.

The 40GB Kingston drive looks promising. I'm hoping that the larger capacity Intel drives will drop in price as well.

Indeed. I think I'll pick one up when it gains TRIM so I can add support that feature in the SSD-as-HDD-cache driver I'm working on. Most of the other smaller SSDs have terrible controllers. Too bad Intel aren't releasing a TRIM-capable firmware for the previous generation of SSDs. (I have the 80GB version of it)

Pardon my ignorance, but can't you just increase the size of the pagefile to consume the ssd and then increase the disk cache? this way the OS can handle memory management as it pleases..

Most OSes don't swap their disk cache, since they assume that reading a page from swap is no faster than reading it from the filesystem.

Correct. Moreover, disk caches in memory don't persist across reboots, which means the first access since OS startup is ALWAYS slow. You also can't return from an fsync() if writes have only been written to non-persistent cache. A persistent cache therefore can help even if you have oodles of RAM. Moreso if you don't.

Hope we're going to see TRIM support on the X25-M G1's. Mine's already showing signs of degraded performance :/

My G1 "broke" and I RMA'd it and they sent me a G2. nothing to see here, move along..

The poor man's TRIM is to copy the entire disk's data elsewhere, do an ATA Secure Erase operation on the SSD, then repartition, format, and copy everything back. No chance of doing it online though.

Intel says the G1 is not getting TRIM.

(I learned my lesson about firmware upgrades when I bought a 28.8 modem that was "fully upgradeable to 33.6" and then the update was never released.)

Does anyone know if Snow Leopard will ever support TRIM? It saddens me that I have to boot into Windows 7 to manually run TRIM on my drive every so often.

Do you have it formatted as FAT32 or NTFS or something? I didn't think Windows had HFS+ support?

Snow Leopard's boot camp adds HFS+ support.

How in the world does Windows know what blocks were used by files that you then deleted in OS X?

You're right. It appears I'm mistaken. I assumed it was more of an issue of cleanup, but it's pretty obvious that running the TRIM utility in Win7 is useless for my Mac partition.

Nonetheless, the question in my post was more of the point. I wish Snow Leopard had TRIM support.

Yeah, if cleaning up were as simple as that, you wouldn't even need OS support, the drive could just trim itself as it went. But it's been 20 years since anybody designed disk geometry into a filesystem, and while TRIM may not be as complicated as all that, it still requires more bookkeeping than the OS usually does.

Optimally using TRIM, such that the OS will defragment the 512K blocks online instead of reusing them, is even more work, and I'm not sure that's what Windows is doing. They're just issuing TRIM opportunistically, AFAIK.

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