Author: W B Hacker Date: To: exim users Subject: Re: [exim] How to force exim to load file with whitelist IPs into
memory
no.spa@??? wrote: > I thought that it could be possible to load lsearch file into memory
> like exim.conf etc is loaded into memory.
>
> So I see that it is not possible, if I properly understand your statement.
>
> Mike.
>
Quite the reverse.
It is not only POSSIBLE, it is probably *automatic* and already being done.
But it is up to the Operating System's Virtual Memeory implementation -
which will load, unload, and reload it (think 'swap', but not only that)
as required to honour such priorities as may arise.
Not just Exim's, but Exim AND all others.
Per Phil Pennock's note, what is confusing the issue is that you are
looking at the file *access* time. That is a 'stamp', an update to the
inode associated with such things.
It does not necessarily mean that the file itself, or even one byte of
it, was loaded or unloaded from/to disk. Primary OR swap.
You only need to put a file into RAMdisk to force it to stay in one
place IF you are convnced you know more about such things than the file
system and Virtual Memory designers.
Trust the experts - it is less work to just mount 'noatime'.
And even LESS work to simply not bother yourself with it at all.
The *queue* is generally your only/most significant resource-sensitive
portion of the file system.
And even that JFW in nearly all cases. By the time one has enough load
to stress the queue, load balancing to a second box is a better idea
than fiddling, simply so you can keep half your users off the phone when
a CPU fan or such quits.
If you want to make a difference, simply insure your WL and BL are as
terse as practical, checked only when they must be, and that searches
utilize as clean and 'light' a syntax as will get the job done.
If you - and your correspondents - are doing everything ELSE right, you
shouldn't need even 50 IP's in a WL anyway.
I've never needed but half that, and usually a quarter or less.
My BL, OTOH, is large primarily so as to NOT have to make a *remote*
callout to published RBL's on always-known-bad offenders. Unless
recently cached, those always take far longer than a stroll through
local RAM.
Also 25K 'large' because I only clean it up about once in every six to
ten years...
There are many OTHER things that will give you a better payback for time
invested.
