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2009/12/20 Disk and Crypt Benchmarks
π 2009-12-20 00:00 in Linux
I migrated my main laptop from a Z61p to a slightly thinner W500. The big plus was not the slightly better CPU or support for more than 3GB of Ram, but the fact that it lets me select a lower performing Intel G450 video card instead of the fast power hungry and not well supported ATI one.
I've managed to get from an uncertain 25W to a 10W by switching to the Intel driver and turning off everything I can outside of the screen. Amazing!

Anyway, the point of this post was to talk about benchmarks. I was curious to know how much faster switching from a 5400RPM drive to a 7200RPM drive would be (I have a 500GB drive, SSD in that size is not too much an option yet, and I'm not really hurting for speed anyway).
The next thing was to see how much dmcrypt was slowing me down.

Ready for it?
dmcrypt gave me virtually no slowdown on a kernel build and a mere 4-5 seconds to get Enlightenment started from boot (about 40 seconds from lilo prompt to Enlightenment loaded and opening its screen with Eterms already loaded). So, I really don't care about 4 seconds of boot time if it makes virtually no difference once the system is running. The best part was that switching from a 160GB 7200 RPM drive without dmcrypt to a 500GB 7200 RPM drive with dmcrypt, opening a maildir folder with 50,000 messages actually went DOWN from 50-ish seconds to 16-ish seconds!

7200 vs 5400RPM gave a modest boot speed improvement (8 seconds) and considering I boot once a month on average, it's really not something I care much for. Opening a maildir folder is faster by a few seconds (15%-ish) but nothing earth shattering. Building a kernel is maybe 20 seconds faster. All this to say that 7200 RPM is not something I would kill or pay load of extra money to get.

Anyway, switching from my old 5400RPM drive with dmcrypt to a 7200RPM drive with dmcrypt (all using ext4 on a freshly layed out filesystem).

Oh, the other test I did quickly was to see whether HIMEM64G (enabling PAE and a 3rd level indirection required for me to see 64GB instead of 3GB), and indeed HIMEM64G is a tad slower than running without HIMEM4G as I had feared, but not by a whole lot (looks like less than 5%), so I'm willing to ignore it.

Raw data below. It shows time from lilo prompt to X starting, and E fully launched as well as how long it takes to open my rcvd and snd maildir folders on a cold cache. Then, I build a full featured kernels with 4 concurrent threads.

5400 RPM 160GB seagate, no dmcrypt, HIMEM64G

boot1: 27 X start / 50 E ready / 0:58 rcvds / 0:52 snd

kernel build #1: real 23m24.829s user 39m59.454s sys 4m16.530s

kernel build #2: real 22m47.524s user 39m52.953s sys 4m16.569s

boot 2: 23 X start / 41 E ready / 0:58 rcvd / 0:34 snd

kernel build #1: real 23m3.003s user 40m2.183s sys 4m17.200s

kernel build #2: real 22m38.859s user 40m0.710s sys 4m21.401s

boot 3: 25 X start / 46 E ready / 0:58 rcvd / 0:34 snd

kernel build #1: real 24m19.828s user 40m1.283s sys 4m35.624s

kernel build #2: real 23m51.198s user 39m58.137s sys 4m37.391s

boot 4: 23 X start / 42 E ready / 0:60 rcvd / 0:33 snd

----------------------------------------------------------------------------

7200 RPM 160GB seagate, no dmcrypt, HIMEM64G

boot 1: 21 X start / 36 E ready / 0:48 rcvd / 0:25 snd

kernel build #1: real 23m22.448s user 39m49.538s sys 4m13.604s

boot 2: 21 X start / 34 E ready / 1:03 rcvd / 0:21 snd

kernel build #1: real 22m58.988s user 39m53.308s sys 4m12.700s

kernel build #2: real 22m43.217s user 39m50.925s sys 4m14.976s

boot 3: 21 X start / 35 E ready / 0:39 rcvd / 0:20 snd

---------------------------------------------------------------------------- 7200 RPM 500GB hitachi, dmcrypt, HIMEM64G

boot 1: 27 X start / 40 E ready / 0:18 rcvd / 0:19 snd (cryptsetup unlock takes a few seconds)

kernel build #1: real 23m14.759s user 39m56.628s sys 4m11.470s

kernel build #2: real 22m46.385s user 39m52.201s sys 4m11.900s

boot 2: 26 X start / 39 ready / 0:14 rcvd / 0:18 snd

kernel build #1: real 23m5.225s user 39m59.785s sys 4m11.592s

real 22m47.208s user 39m52.411s sys 4m11.155s

---------------------------------------------------------------------------- 7200 RPM 500GB hitachi, dmcrypt, HIMEM4G boot 1: 24 X start / 36 ready / 0:14 rcvd / 0:20 snd

build #1: real 23m0.698s user 39m45.571s sys 4m3.892s

build #2: real 22m39.361s user 39m42.988s sys 4m3.924s


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