TCP_IMS_HIT - from disk always ?

[Michael Pye <michael@xxxxxxxxxx>]

Some analysis of squid (2.5stable12, compiled using sun studio cc) using 
dtrace on solaris10 shows in my acclerator setup that there are large 
numbers of READ system calls apparently to small files in the cache 
directory. These are hits to images that clients have and are sending 
If-Modified-Since requests, so the log shows lots of TCP_IMS_HIT accesses.

The amount of reads to these small files though indicates that these 
files are read everytime. Is there not a way to get these into memory so 
the TCP_IMS_HITs can be answered from memory rather than from disk? I 
still have minimum_object_size to 0 and a large enough 
maximum_object_size for this to be in memory. In fact the object is in 
memory as clients that don't send IMS requests do get the object via a 
TCP_MEM_HIT. Is there some reason why IMS requests are not answered from 
memory ?

Thanks,

--
Michael Pye