Re: [squid-users] Squid 2.x maximum_object_size related to memory usage

Adrian Chadd wrote:
> On Fri, Jul 27, 2007, rihad wrote:
>
>> Ok, now I understand that, if you have cache_mem of, say, 300 mb, it's
>> never a good idea to make maximum_object_size = 64 MB as an average of
>> 10-20 concurrent downloads will surely fill the memory. I hoped Squid
>> would only keep in memory the buffer (up to read_ahead_gap) necessary
>> for relaying the file being downloaded to the client, while still
>> writing it on the disk in the process.
>
> The memory cache and the disk cache are pretty seperate. squid can
> remove a memory from being in the "memory cache" (ie, the whole object
> is in memory) whilst still writing it to disk as it comes off the
> network.
>
> I don't believe anyone's done much work investigating Squid's behaviour
> with small and large memory objects.
>
>
>

Let me be the pioneer ;-)

KEY 83FC85024B526D35AD958302B5253591
        GET http://example.com/path/to/large.file
        STORE_PENDING NOT_IN_MEMORY SWAPOUT_WRITING PING_DONE
        CACHABLE,DISPATCHED,VALIDATED
        LV:1185550831 LU:1185550831 LM:1185513900 EX:-1
        5 locks, 1 clients, 1 refs
        Swap Dir 0, File 0X0D6F8D
        inmem_lo: 10432512
        inmem_hi: 10485475
        swapout: 10481664 bytes queued
        swapout: 10481843 bytes written
        Client #0, 0x0
                copy_offset: 10432820
                seen_offset: 10432820
                copy_size: 4096
                flags:

About inmem_lo and inmem_hi: aren't they saying there's currently
inmem_hi - inmem_lo bytes buffered in memory, and that the file is being
written to disk on-the-fly (SWAPOUT_WRITING)?
Received on Fri Jul 27 2007 - 11:32:13 MDT