performance drop moving from 3.0 to 3.1?

[david@xxxxxxx]

I'm using squid in a pure access control mode (all caching disabled) and 
am looking to move from 3.0 to 3.1, but when I'm doing lab tests with it I 
am seeing a significant performance drop.

when doing a simple small request test (using ab to hammer the proxy 
retrieving 40 byte pages) 3.0 is reaching 4200 request/sec while under the 
exact same conditions 3.1.11 is barely topping 1400 requests/sec.

if I request larger pages (100K), 3.0 does ~650 requests/sec while 3.1 
only manages ~480 requests/sec. going up to 1M pagess, 3.0 does 90 
requests/sec while 3.1 does 60

this is with identical configuration except that 3.0 has the null disk 
cache driver configured while 3.1 has that line commented out.

In all of these cases, squid is maxing out at 100% of the single core it 
has available to it.

David Lang