Indexing Mail faster

[Kevin Laurie]

Dear Marc,
Noted.
This is starting to make a lot of sense. Of course, more computing power,
hence more performance.
Also filesystems and such all have and effect on the outcome. I might
experiment with adding more computing power and seeing the result.
My mailbox does not have many users so I might try that. Currently running
a 2gb RAM with 2core processors.



On Thu, Jan 29, 2015 at 4:23 PM, Marc Stürmer <mail at marc-stuermer.de> wrote:

> Am 27.01.2015 um 03:24 schrieb Kevin Laurie:
>
>  Hi Thomas,
>> That's very interesting.
>> Below is my search result. Any idea why is my result so slow:-
>> Appreciate if you could advise.
>>
>
> It depends on a couple of facts. Full text searches must go through a
> number of bottle necks, depending on your installation, namely:
>
> a) type of disk drive(s),
> b) way of installation of those drives,
> c) the underlying file system itself,
> d) the storage format being chosen to save the mails,
> e) how many users you've got on your system,
> f) memory of your system,
> g) CPU power of your system and
> h) how busy your system is.
>
> If you got for example a lonely box with let's sax four gigs of RAM and
> you are using it by yourself only, chances are high enough that even with a
> big enough up time most of your mails are in the file system cache of your
> OS. Meaning a full text search would happen mostly in RAM and therefor of
> course would be blazingly fast.
>
> If you take the same machine and let it serve let's say about 2000
> mailboxes, this would be a very different kind of matter. Your file system
> cache would be flushed frequently and full text searches without index
> would be way slower, because now those search actually mean I/O operations
> for Dovecot on your type of storage.
>
> If you really want consistent, fast full text search speeds on a busy box,
> incremental full text indexing is the only way to go.
>
> If you are the only user of a big box chances are high you get similar
> results without.
>