On Jun 4, 2007, at 8:06 PM, Jake Anderson wrote:
[EMAIL PROTECTED] wrote:
Sounds migratory...
But it might be the best approach.
I think at the current state of the art the following is
reasonably true:
SHA1/MD5 is fast enough for the typically allowed file sizes in a
mail
system (10MB) given the frequency with which they occur.
If someone has a future need of 100MB or 10GB file sizes as the
norm then
we can also expect to be looking a quad-core also being the norm --
making all things equal.
If they have a current need for 100MB files, then they probably
already
have a really big server at their disposal.
One thing I do like about dbmail is the scalability. I interpret
this to
mean both small and large mail environments can use with application
with existing or reasonably hardware. To require super huge machines
for a personal domain isn't very scalable.
Like I said a P4 2.6Ghz core will handle sha at 50 mbytes per second
using about 20% of a cpu IE its disk limited (by a 15krpm scsi
disk) so
a 100mb email will take 2 seconds to sha if its being read off
disk. If
its being done at wire speed (IE coming in over a 100mbit ethernet
line)
then the additional burden of the sha will be about 3% at 100% line
use.
Really it is totally insignificant if you have any sort of spam
filtering or in fact any sort of anything. In a common dual core setup
you are talking 1.5% extra cpu load and at the same time you could
potentially drastically reduce the disk load.
However and whatever is done, it shouldn't be based on a narrow set
of assumptions to the expense of others.
I'm not saying it doesn't have merit to take 100MB email into
consideration.
But as you've mentioned before, the current practice you've seen is
not 100MB email delivery but 100MB email as a file storage system
(Draft).
And at the same time you state the 100MB will take to 2 seconds to
SHA and that's small compared to the overall processing speed of mail
delivery. And this is not significant when filtering spam.
But as yet, no one filters 100MB email as spam. It's just delivered
(if it wasn't a Draft) Most filters bypass at 1MB and under 1MB the
time to filter is <1second for me and my spam_filter.
So what you have is a 100MB possibility as a Draft that isn't checked
for spam, wouldn't be anyways, isn't delivered, or any sort of anything.
These are small times, but they start to add up.
I really like dbmail. But I'm not a large scale environment. I
don't have a dual core anything. I currently have only four
accounts. But for these four accounts it is one of the best
performing applications I've used, and I've tested a lot of them.
I'm just asking that we keep in mind that while 100MB might be
something to keep in consideration going forward, don't lose the
sight of the smaller users for your sake.
_______________________________________________
DBmail mailing list
[email protected]
https://mailman.fastxs.nl/mailman/listinfo/dbmail
