Re: [PATCH] nnimap performance improvement for large or old groups

[Daniel Pittman <daniel@rimspace.net>]

Simon Josefsson <jas@extundo.com> writes:
> Daniel Pittman <daniel@rimspace.net> writes:
>
>> One of the nagging problems with using nnimap as my primary mail store
>> is that it takes absolutely forever to enter my INBOX, as well as
>> causing XEmacs to allocate around 150MB of memory.
>>
>> This is because I have been using the same INBOX for a long while now,
>> and the 'read' info range starts with '(1 . 695705)'
>>
>> The code in `nnimap-request-update-info-internal' called
>> `gnus-uncompress-range' on this, resulting in a list containing around
>> seven million numbers -- an awful lot of memory, and time spent working
>> through it.
>>
>> To address this I rewrote the code in that routine to work with
>> compressed ranges, rather than uncompressed, which gives me a huge
>> performance improvement (almost instant entry, vs ten to fifteen
>> seconds) and reduces the memory use significantly.
>>
>>
>> I don't think this is too performance-inefficient to include as is, and
>> it doesn't seem to adversely effect entry into small groups or anything
>> like that.
>
> Your patch seem correct.  Installed, thanks!
>
> It should probably be tested for a while before being included in
> v5-10 though, the logic seem somewhat complicated and while I
> convinced myself that it does the same thing, I might be mistaken.

I completely agree that this should have long and thorough testing, for
all that I did very carefully check the way that it worked, and made
sure to verify every step of the new computation manually.

Oh, but it surely is *nice* to have that in there, though. :)

    Daniel