A quick and easy performance improvement

[Alex Neuman van der Hans]

There are a lot of things people wish MailScanner would do that can 
easily be accomplished outside of the MailScanner system. It reminds me 
of the discussions in firewall-related mailing lists where there is a 
small group of people that wish their firewall would do things outside 
the scope of a firewall (vs. for example, a security appliance with a 
built-in firewall).

I think as long as people keep updating the wiki with "this three step 
procedure improves this process by this much" (like putting 
/var/spool/MailScanner/incoming in a ramdisk) articles, JF can focus on 
providing more and better core functionality.

Julian Field wrote:
> A lot more suitable would be a cron job you could easily write to back 
> it up to another location every hour or so.
> It would be harder to configure it to do it in MailScanner than it 
> would be just to write the cron job yourself. It's only 1 cp command.
>
> Chris Hammond wrote:
>> Maybe this could be a new feature request?  Have MailScanner copy the 
>> bayes db that are used by SA that is being called by it to memory and 
>> then sync back to the drive at low disk IO times or a maximum time, 
>> which ever comes first?  Or am I out in left field somewhere?  Oh 
>> wait, don't answer that......
>>
>> Chris
>>  
>>>>> Richard Lynch <rich at mail.wvnet.edu> 07/26/06 12:25 PM >>> 
>> uxbod wrote:
>>
>>> Why not hold the bayes on a RAM partition, and have a cronjob that 
>>> periodically backs it up throughout the day so that changes are not 
>>> lost if the server crashes ?
>>>  
>>>
>>
>> That would definitely improve things.  Seek time in RAM is zero!
>>
>> While monitoring disk I/Os (iostat 1) I was surprised at the high 
>> number for bayes.  I didn't expect to see it so high.  One my systems 
>> it was actually higher than the I/O for the mail queues.
>>
>> -- Rich
>>
>>> On Wed, 26 Jul 2006 11:21:57 -0400, Richard Lynch 
>>> <rich at mail.wvnet.edu> wrote:
>>>  
>>>
>>>> Nathan Olson wrote:
>>>>
>>>>   
>>>>> Would noatime affect bayes operation on /var/spool?
>>>>>
>>>>> Nate
>>>>>
>>>>>     
>>>> Noatime will probably help since it would reduce the number of I/O
>>>> operations to the disk -- fewer I/Os is good for performance.  If I
>>>> recall correctly, noatime means that the system will not update the 
>>>> last
>>>> access date for the file.  One less I/O will certainly help.  The
>>>> benefit I'm going after comes from reducing disk seek time by putting
>>>> the bayes DB closer to the mail queues.  For me, using pretty much a
>>>> default installation, the benefit was in decreasing the IOWait time to
>>>> 1/10th that value it was.
>>>>
>>>> -- Rich
>>>>
>>>> -- 
>>>>
>>>>
>>>>
>>>>
>>>>   
>>>
>>>  
>>>
>>
>>
>