[squid-users] ufs vs. diskd performance

Hello,

I run squid servers with the same config on two FreeBSD-4.9 machines (with
the same HW/SW). Squid version is 2.5STABLE5 with some patches (installed
from FreeBSD ports, to they're mostly official squid patches I'd say).

I tried to increase performance of squid by using diskd, but I noticed
that it does NOT change too much in currect configuration.

What seems to be worse, it seems that squid performance decreased a bit
with diskd. Especially service times for cache misses, and ICP replies to
another caches.

I'd like to ask - is that normal? Service times are not high, but I would
not expect times to increase.

It is probable that the performance boost can only be notices on loaded
caches (our caches are not loaded much this time). Is that right?
I found bug 355 (http://www.squid-cache.org/bugs/show_bug.cgi?id=355)
which talks about slow responses for cache hits...

Can anyone confirm/comment this issue?
Thank you much.

some statistics from 2. caches running (nearly) the same time below.

cache with diskd:

Median Service Times (seconds) 5 min 60 min:
        HTTP Requests (All): 0.05046 0.05951
        Cache Misses: 0.24524 0.23230
        Cache Hits: 0.01387 0.01235
        Near Hits: 0.05331 0.03241
        Not-Modified Replies: 0.00463 0.00678
        DNS Lookups: 0.00464 0.00779
        ICP Queries: 0.00000 0.00067

cache without diskd:

Median Service Times (seconds) 5 min 60 min:
        HTTP Requests (All): 0.15048 0.09219
        Cache Misses: 0.17711 0.15888
        Cache Hits: 0.02069 0.01745
        Near Hits: 0.17711 0.06286
        Not-Modified Replies: 0.02317 0.01955
        DNS Lookups: 0.04639 0.02336
        ICP Queries: 0.00039 0.00356

note the increased service time for cache misses...

Also, as long as those two are siblings to each other:

cache with diskd (as seems from cache without diskd):

Sibling : proxy-sibling1/3128/3130
Flags : proxy-only
Address[0] : 195.168.1.101
Status : Up
AVG RTT : 9 msec
OPEN CONNS : 0
LAST QUERY : 1 seconds ago
LAST REPLY : 1 seconds ago
PINGS SENT : 493334
PINGS ACKED: 492225 100%
FETCHES : 15170 3%
IGNORED : 237598 48%
Histogram of PINGS ACKED:
         ICP_HIT : 862 0%
        ICP_MISS : 491363 100%

cache without diskd (as seems from cache with diskd):

Sibling : proxy-sibling1/3128/3130
Flags : proxy-only
Address[0] : 195.168.1.102
Status : Up
AVG RTT : 1 msec
OPEN CONNS : 0
LAST QUERY : 0 seconds ago
LAST REPLY : 0 seconds ago
PINGS SENT : 491944
PINGS ACKED: 490930 100%
FETCHES : 15739 3%
IGNORED : 369896 75%
Histogram of PINGS ACKED:
         ICP_HIT : 696 0%
        ICP_MISS : 490234 100%
keep-alive ratio: 100%

Note the average RTT increased...

-- 
Matus UHLAR - fantomas, uhlar@fantomas.sk ; http://www.fantomas.sk/
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