the first was kicked by by the announcement that pbzip2 is available on sunfreeware. Now, bzip2 is pretty cpu intensive, so if there's a way of making it go faster then I'm all for it.
So here are some figures - in seconds - for pbzip2 as a function of the number of cpus used. I've used a small blocksize (100K) rather than the default, which helps as the test file isn't all that big.
| # cpus | Time |
|---|---|
| 1 | 16.444 |
| 2 | 8.686 |
| 4 | 4.287 |
| 8 | 2.791 |
| 16 | 1.821 |
| 32 | 1.784 |
That's pretty good. I would expect to get approximately a factor 8 gain here: it's a cpu intensive application and there are 8 physical cores. So we see about a factor 9, which is pretty good.
My next test was to load up an apache/php/mysql combo and see how that goes. The comparison machine is a SunBlade 2000 with a pair of 1.015GHz processors. (Note: this is using the same binaries - not optimised code on the T2000. Yes, Sun have optimised binaries, but that isn't really helpful in comparison, as with most applications a recompile wouldn't be feasible.)
For a simple database query operation, the T2000 took 0.160s as opposed to the 0.112s. For generating a graph, the T2000 was again slightly slower - 9.538s against 7.167s.
Again you see the single-threaded performance is at about the 60-70% of a regular UltraSparc cpu of the same clockspeed. But, this thing has 8 cores, how well does that work?
So I fired up the apache benchmark ab. And just for the database retrieval report I can get about 30 pages per second out of the SunBlade, but (with 32 concurrent requests) about 100 pages per second out of the T2000. And - according to top - the T2000 is only 50% busy. In fact, my server (apache/php/mysql) setup croaks if I push it much harder (but then it's a reporting thing designed for 1 page a minute).
So, on this test the T2000 is at least as good as 3 SunBlade 2000s. Or,equivalently, it's better than an 8x750MHz V880. Which is pretty good, as it's a fair amount cheaper and smaller.
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