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!AX == good / ZFS on purple.the-7.net

This is the first year I skipped AX in God knows how many years, yet I feel all good and dandy and relaxed at home.  :D

Oh, by the way, purple.the-7.net has seen the light and converted to ZFS (except for /boot, which needs to be still in UFS because the boot loader is too stupid to handle ZFS yet).  I'm amazed how its performance rivals that of UFS2, even with all the extra features comes with it.  Gotta commend Sun Microsystems for releasing this amazing piece of code in open source.  :D

The LTO-2 drives in purple.the-7.net and seerajeane.astralblue.net (my bedroom computer) are awesome.  I'm copying/restoring purple:/pub onto seerajeane:/pub (which is on a dedicated RAID5 array and runs ZFS too), and the bottleneck is not the tape drive but the hard drive.  Modern tape drive technologies never cease to amaze me….  I mean, LTO-2 isn't even the newest generation of LTO technology (there's LTO-4 now, which boasts the throughput of 120MB/sec, which is faster than usual hard drives these days can handle)!

Speaking of ZFS, it's godly also because it spreads writes across the entire disk over time (it's called “wear leveling”) can detect bad sectors on the fly and adjust accordingly; it means it can run on top of a flash drive, whose memory cells (sectors) has a finite lifetime in terms of write operations.  My home router is now a Soekris net5501 box with a CompactFlash disk in it, and I can safely use read-write filesystems without having to worry about wearing the disk off in 10 months (it had happened to me once), thanks to ZFS.  ♥

Comments

Wear levelling is built into ZFS? I was not aware of this. Link?

I tried using ZFS on FreeBSD, but sending a snapshot stream from one drive to another box caused a kernel panic. This was shortly after 7.0-RELEASE went out. Maybe it's changed now, but I've spent enough time figuring out how to make my craptastic hardware work under OpenSolaris to not want to change it. :)
Oh, and while I'm at it...

A) When did purple get moved to HE? (And are you colocating individually, or... oh, I see.)

B) What kind of connection do you have at home that's fast enough to saturate a hard drive!?
A) Quite a while ago (it's been two years at least, maybe more; I forgot).
B) Out-of-band connection (aka LTO-2 tapes). XD
Ah, I see. I did some digging and saw DDR Freak now gets served out of there. Do you guys rent a half-cab or something?

I used to have a server colocated at HE via communitycolo.net, or the CCCP, as we called it. Sadly, the CCCP went under, and now I'm in with Cernio at UnitedLayer. I do like HE's plethora of connections, though.
A quarter cab (7U)... Almost maxed out with 2 2U servers and a tape jukebox. XD
Dang. Guess that answers my other question: got any space? XD
I did some more digging and it seems I was wrong; wear-leveling is built not into ZFS but into flash drives themselves these days (in order to handle primitive filesystems such as FAT32, whose FAT and filesystem summary area need to be rewritten every time something is modified on the disk).  On the other hand, ZFS can detect write failures and push the sector out of service as necessary.
Ah, yeah, that makes more sense. Yeah, standard CF devices that present themselves like IDE/ATA devices will typically hide the wear-levelling logic on the inside. I know of flash filesystems, but they're more for direct NAND flash chip access.

I've so far liked ZFS. My only quibble with it is that it is presently impossible to use its ACL system to set up a completely wide open file share. (Which is bad, security-wise, but horribly convenient for home use.)
"This is the first year I skipped AX in God knows how many years, yet I feel all good and dandy and relaxed at home. :D"

Damn, you too? Ever since I started going in 1999, I never missed it, and it was always a perennial event. Well, until I just didn't give a crap this year and didn't go.

Perhaps we should meet up and celebrate NonAX 2008 :D

feeling good and dandy and relaxed at home is the way to go. keep up those midnight blue sessions... :D
I didn't go to AX this year, too. So far, it sounds like it's gonna be every 2 years for me. =P