Re: cache_mem at version 1.1.14

On Wed 10 Sep, 1997, "Thomas Krause" <tom@deh.de> wrote:
>I've build a transparent proxy with Linux 2.0.29,
>128 MB RAM and a 7.3 GB partition for squid (ver. 1.1.14)
>In squid.conf I set cache_mem to 48 MB, but the
>squid uses about 160 MB - so the proxy becomes slow.
>Why does the proxy uses so much more memory?
>Should I decrese the value of cache_mem?

My general experience gained from running Squid 1.1.x on Irix 6.2 and FreeBSD
2.2.x has been that with 7GB of cache disk (cache_swap), and 96MB cache_mem,
processes will grow to around 180-190MB. Certainly once I grafted the malloc
from FreeBSD into my Irix build (see previous posts to this list where this has
been discussed) it too remained stable.

Thus, a combination of Squid 1.1.x, 256MB in the machine, and 7GB of disk
spread across multiple spindles (we actually have disk arrays that are much
larger - but that was because we had them anyway, and it was a good number of
spindles).

We've not really made an effort to assess how important that 96MB setting is
and whether we could go larger or smaller. We run with a swap low/high of
90/91% (setting them equal leads to a divide by zero bug..), and a mem low/high
of 75/90%.

Right now, one of the systems looks like:

Cache information for squid:
        Storage Swap size: 6335 MB
        Storage Mem size: 72188 KB
        Storage LRU Expiration Age: 3.57 days
        Requests given to unlinkd: 101048
        Unused fileno stack count: 37
Resource usage for squid:
        CPU Time: 18426 seconds (8644 user 9782 sys)
        CPU Usage: 4%
        Maximum Resident Size: 178248 KB
        Page faults with physical i/o: 4
Internal Data Structures:
        501139 StoreEntries
          2076 StoreEntries with MemObjects
          2076 StoreEntries with MemObject Data
          2061 Hot Object Cache Items
Accounted Memory Usage:
        StoreEntry 501139 x 52 bytes = 25448 KB
        URL strings = 23582 KB
        IPCacheEntry 920 x 36 bytes = 32 KB
        FQDNCacheEntry 0 x 56 bytes = 0 KB
        Hash link 2061 x 12 bytes = 24 KB
        Pool MemObject structures 2076 x 96 bytes = 194 KB ( 0
free)
        Pool for Request structur 257 x 4792 bytes = 1202 KB ( 758
free)
        Pool for in-memory object 22905 x 4096 bytes = 91620 KB ( 14600
free)
        Pool for disk I/O 51 x 8192 bytes = 408 KB ( 344
free)
        NetDB Address Entries 0 x 76 bytes = 0 KB
        NetDB Host Entries 0 x 8 bytes = 0 KB
        NetDB Peer Entries 0 x 24 bytes = 0 KB
        ClientDB Entries 7172 x 292 bytes = 2045 KB
        Miscellaneous = 4032 KB
        Total Accounted = 148590 KB

That's the picture after 5 days, because we've been making some configuration
changes that needed a complete restart, but it's pretty much the stable state
that is reached by each of our Squid running systems.

James.
Received on Wed Sep 10 1997 - 14:35:13 MDT