Disk Benchmarks

May 23rd, 2008, 12:02 pm PST by Greg

I recently decided that I needed more space to backup/archive data. So, I went out and bought a terabyte external drive ($240 at Costco). This drive is a WD MyBook Studio, which happens to come with USB, FireWire, and eSATA connections. I started to wonder how different those connections really are. The theoretical bandwidth of each is 60MB/s, 50MB/s, and 384MB/s, respectively.

First of all, I could have sworn my motherboard had a eSATA connector, but it doesn’t. So, that’s out.

I decided to do some benchmarking with Bonnie++. This seems to be the standard Linux disk benchmarker. I used the default configuration for all the tests, since I figure they knew what they were doing when they decided what the defaults were.

After seeing an FAQ about benchmarking RAID, I decided to also try tiobench. It tests multithreaded IO performance. I decided to look at 2 threads doing sequential reads and writes.

Then, I started to wonder how these stacked up against my internal drives. SATA is back, but internal, and with a different disk on the end. I have two internal drives, both 400 GB, 7200 RPM, 16MB cache. They are used along with the Linux software RAID stuff to create a RAID 1 (for even moderately important stuff) and a RAID 0 (a big bit bucket).

I also tried a straight-up non-RAID partition on an internal disk (and I had to temporarily degrade my RAID to do it—I hope you appreciate this). The last tests I did were on my laptop and its 60 GB, 5400 RPM disk.

Here’s what I came up with. In all cases, larger numbers are better.

Disk Benchmarking Summary
Disk Bonnie Block Read (MB/s) Bonnie Block Write (MB/s) Bonnie Seek (/s) tiobench Read (MB/s) tiobench Write (MB/s)
SATA non-RAID 70 54 250 44 46
SATA RAID 1 53 45 366 54 37
SATA RAID 0 62 89 207 43 56
External USB 32 29 172 29 28
External Firewire 37 33 188 32 32
Laptop internal 20 23 94 18 18

[Intel D975XBX motherboard, Intel Core 2 Duo 6600, 2GB RAM, Ubuntu Hardy, relatively idle system, ReiserFS 3.6 partitions. Laptop is a Pentium M 1.86 GHz, 512 MB RAM, Ubuntu Hardy, idle, EXT3 filesystem.]

So… what did we learn from that?

  1. I’m too lazy (and non-visual) to bother making useful graphs in situations like these.
  2. USB 2.0 and Firewire are close enough in speed that it’s not worth mentioning.
  3. Damn, I wish I had eSATA on my motherboard to see how that fared.
  4. If possible, keep your disks inside the computer where they belong. The external performance is pretty impressive, but much slower than internals.
  5. … unless your other option is a slow laptop drive, then the externals start to look pretty snappy. I didn’t try the external connected to the laptop, though. There might be a processor/bus bottleneck.
  6. The RAID arrays aren’t nearly as fast as I thought they’d be. This could be a result of the Linux software RAID slowing things down. I have never used hardware RAID controllers (either the ones on many motherboards or dedicated cards).
  7. Seriously… who’s stealing all my RAID performance? I want it back!

Edit [05/23]: I feel I should add: All benchmarks are crap. They are positively correlated with the thing you want and call “performance”, but are definitely not directly related.

Marital Rating Scale

May 14th, 2008, 12:13 am PST by Greg

Boing Boing just had a post on a 1939 marital rating scale for wives. The obvious question in a case like this is: how does my wife score on this scientific rating?

Only one way to find out… (Points up for grabs in square brackets. Points given at end of commentary. )

Demerits

  1. Slow in coming to bed—delays till husband is almost asleep. [1] Generally goes to bed before me. Does that count? Probably. -1
  2. Doesn’t like children. [5] She kind of does, but I don’t. Again, the condition is pointing in the wrong direction. I’ll take off partial points: -2
  3. Fails to sew on buttons for darn socks. [1] Never. -1
  4. Wears soiled or ragged dresses or aprons around the house. [1] Two words: flower pants. Taking extra points for those. -2
  5. Wears red nail polish. [1] Nope. -1
  6. Often late for appointments. [5] “I’ll meet you in five minutes.” Yeah right. -5
  7. Seams in hose often crooked. [1] Not applicable? She does have that one pair of sweatpants that don’t sit right (because they were “cheap”). I think that falls under number 4, though. 0
  8. Goes to bed with curlers on her hair or much face cream. [1] There are a lot of creams, but not visible when going to bed. 0
  9. Puts her cold feet on husband at night to warm them. [1] Oh god, how do feet get that cold? Extra demerits: -2
  10. Is a back seat driver. [1] Only complains when I say things like “gonna die” while in the process of a dodgy left-hand turn. Reasonable since she’s the one exposed to oncoming traffic in that situation. 0
  11. Flirts with other men at parties or in restaurants. [5] Any flirting likely negated by mine. 0
  12. Is suspicious and jealous. [5] I will give her this one: I’m a tool, but she trusts me. Giving a point back. +1 [N.B. Her trust is well-deserved.]

Merits

  1. A good hostess—even to unexpected guests. [1] Yeah, she’s good like that. It’s the Filipino side. When left alone in the house for extended periods, I can only offer unexpected guests delicacies such as filtered water and ketchup. +1
  2. Has meals on time. [1] Not particularly. Sometimes I even have to cook! 0
  3. Can carry on an interesting conversation. [1] Often goes on about boring science stuff, but is generally interesting enough. Tie goes to the runner: +1
  4. Can play a musical instrument, as piano, violin, etc. [1] Her mother bought her a piano, and then she decided she didn’t want to play. For her mom: 0
  5. Dresses for breakfast. [1] Pffft. 0
  6. Neat housekeeper—tidy and clean. [1] Better than me, but not particularly so. 0
  7. Personally puts children to bed. [1] Not applicable. I’ll give it to her: +1
  8. Never goes to bed angry, always makes up first. [5] We’re not big fighters. Sure, why not? +1
  9. Asks husband’s opinions regarding important decisions and purchases. [1] Hrm. A real split decision here. She often buys crap (and more crap) without telling me (or actively hiding it from me). These are rarely “important” purchases, though. I’m nothing if not generous: +1
  10. Good sense of humor—jolly and gay. [1] I’ll leave “gay” alone. She’s a funny one. +1
  11. Religious—sends children to church or Sunday school and goes herself. [10] Oh, you hate to see that many points slip through her fingers: 0
  12. Lets husband sleep late on Sundays and holidays. [1] I often wake up before her, but I suppose she would let me sleep in. +1

If I’m doing the arithmetic right, that comes out to -6. Ouch.

The brief article doesn’t provide any guidance on how I’m supposed to interpret the results. You probably have to pay for that: that’s how they get you. The negative number can’t be good, though. [Edit: Oops… it’s in the original image.]

I’m sure that if I really worked at the scores, I could get her up to zero. Frankly, I’m too tired (and a little drunk) to do that now. Too bad, because I am actually rather fond of her.

[Kat: Please note that there’s an implicit demerit for beating your husband to death after assigning you a score on this scale.]

Edit: Somebody posted the full booklet on Flickr. On the analogous first page of the husband’s scale, I’d say I come out perhaps slightly better. Go me!