IMHO, everyone should delete the softlimit program from their servers 
immediately.  Not that I have a strong opinion on the matter or anything. :)

The softlimit program seems like a good idea -- set an upper limit on the 
amount of RAM a program can use, to guard against memory leaks (but not buffer 
overflows).  In practice however, it causes far far more problems than it 
causes.  When a program hits the limit, it always happens inside a library 
function and not the application itself.  So the user sees strange errors from 
glibc or OpenSSL functions that are never related to memory allocation.  Those 
errors always look like real bugs, because there's never any indication the 
limit was hit.

There's also no way to even estimate how much memory is "correct".  Does anyone 
really understand how many libraries a program loads and how much memory they 
need?  spamdyke uses OpenSSL and on some systems, separate libraries for math 
and DNS functions.  Unpatched qmail doesn't use many libraries, but if patches 
have been applied to allow TLS or authentication, it may use many (who uses 
unpatched qmail anyway?).  If vpopmail is in use, it may need MySQL, depending 
on how it was compiled.  If the server is configured to use stack guarding or 
memory profiling, the virtual memory use could be astronomical.  Every guide 
I've ever read says to use trial-and-error to find the lowest value that 
appears to work, then double (or triple) it.  Crazy!

I've spent way way too much time trying to track down "bugs" that were caused 
by softlimit and I finally reached my own limit this year.  That's why spamdyke 
5.0.1 examines the limits it starts with and, if it can, resets them.  It can't 
undo "hard limits" set by the ulimit program, but it can (and does) undo 

-- Sam Clippinger

On Jun 20, 2015, at 2:05 PM, Philip Rhoades via spamdyke-users 
<> wrote:

> People,
> I played around with the logging verbosity and found if I used debug mode I 
> saw suggestions (commands!?) in the log about remove the softlimit function 
> from the start script for qmail-smtpd - while I was trying to sort out the 
> last bug that was preventing eQmail from working, I did actually do that - is 
> the softlimit function even necessary these days on a lightly loaded server 
> with 8GB RAM?
> Thanks,
> Phil.
> -- 
> Philip Rhoades
> PO Box 896
> Cowra  NSW  2794
> Australia
> E-mail:
> _______________________________________________
> spamdyke-users mailing list

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