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Quick way to see request time distribution

Note: This article was originally published at Planet PHP on 11 January 2011.
Planet PHP
Ever wondered what's hiding behind those average numbers in Pinba reports?
Well, so have we. I spent some time and came up with this result:

0.00: (612, 0.99%)
0.05: ** (2239, 3.62%)
0.10: ****
(3401, 5.51%)
0.15: **************************************** (25431, 41.17%)
0.20: ************ (7806, 12.64%)
0.25: ********
(5823, 9.43%)
0.30: **** (3347, 5.42%)
0.35: ** (1505, 2.44%)
0.40:
(1091, 1.77%)
0.45: **** (2951, 4.78%)
0.50: ** (1238, 2.00%)
0.55: (1019, 1.65%)
0.60:
(746, 1.21%)
0.65: * (662, 1.07%)
0.70: (575, 0.93%)
0.75: (486, 0.79%)
0.80: (381, 0.62%)

So what do we see here? Even though the average request time is 0.308 sec, the majority of the users actually get served faster than that - in about 0.10-0.25 sec.
There's also an interesting peak at 0.45 sec, I'll have to use conditional reports to explain it.
And here is the script I used.