Current CPU usage

Where's the CPU going?

Here's an oprofile output from a very naive custom polygraph workload, ~ 1000 requests a second, ~14kbyte objects. MemPools are disabled; Zero buffers are off so the majority of the allocations aren't zero'ed.

Note that somehow, memPoolAlloc takes 4% of CPU even with memory pools switched off. The allocations still go via the pool code but deallocations aren't "cached". What the hell is taking the 4% of CPU time?

CPU: AMD64 processors, speed 2613.43 MHz (estimated)
Counted CPU_CLK_UNHALTED events (Cycles outside of halt state) with a unit mask of 0x00 (No unit mask) count 100000
samples  %        image name               symbol name
176014    6.7039  libc-2.6.1.so            _int_malloc
160779    6.1236  libc-2.6.1.so            memcpy
128371    4.8893  libc-2.6.1.so            malloc_consolidate
123734    4.7127  squid                    memPoolAlloc
101514    3.8664  libc-2.6.1.so            free
76772     2.9240  libc-2.6.1.so            _int_free
55696     2.1213  libc-2.6.1.so            malloc
55681     2.1207  libc-2.6.1.so            vfprintf
50245     1.9137  libc-2.6.1.so            calloc
48095     1.8318  squid                    httpHeaderIdByName
41172     1.5681  libm-2.6.1.so            floor
37573     1.4310  libc-2.6.1.so            re_search_internal
37434     1.4258  libc-2.6.1.so            memchr
36536     1.3916  squid                    xfree
30646     1.1672  libc-2.6.1.so            memset
30576     1.1646  squid                    memPoolFree
30108     1.1467  squid                    headersEnd
28626     1.0903  squid                    httpHeaderGetEntry
26668     1.0157  squid                    storeKeyHashCmp
...