[olug] Argh!

[Brian Roberson]

in case you dont have man pages installed...


ulimit [-SHacdflmnpstuv [limit]]
              Provides  control  over  the resources available to
              the shell and to processes started by it,  on  sys­
              tems  that  allow such control.  The value of limit
              can be a number  in  the  unit  specified  for  the
              resource,  or  the  value unlimited.  The -H and -S
              options specify that the hard or soft limit is  set
              for  the  given  resource.   A hard limit cannot be
              increased once it is  set;  a  soft  limit  may  be
              increased  up  to  the value of the hard limit.  If
              neither -H nor -S is specified, both the  soft  and
              hard limits are set.  If limit is omitted, the cur­
              rent value of the soft limit  of  the  resource  is
              printed,  unless the -H option is given.  When more
              than one resource is specified, the limit name  and
              unit  are  printed before the value.  Other options
              are interpreted as follows:
              -a     All current limits are reported
              -c     The maximum size of core files created
              -d     The maximum size of a process's data segment
              -f     The  maximum  size  of  files created by the
                     shell
              -l     The maximum size that  may  be  locked  into
                     memory
              -m     The maximum resident set size
              -n     The  maximum number of open file descriptors
                     (most systems do not allow this value to  be
                     set)
              -p     The  pipe  size in 512-byte blocks (this may
                     not be set)
              -s     The maximum stack size
              -t     The maximum amount of cpu time in seconds
              -u     The maximum number of processes available to
                     a single user
              -v     The   maximum   amount   of  virtual  memory
                     available to the shell

              If limit is given, it is the new value of the spec­
              ified resource (the -a option is display only).  If
              no option is given, then -f is assumed.  Values are
              in 1024-byte increments, except for -t, which is in
              seconds, -p, which is in units of 512-byte  blocks,
              and  -n  and  -u,  which  are unscaled values.  The
              return status is 0  unless  an  invalid  option  is
              encountered,  a  non-numeric  argument  other  than
              unlimited is supplied as limit, or an error  occurs
              while setting a new limit.





----- Original Message -----
From: "Sam Tetherow" <tetherow at nol.org>
To: <olug at olug.org>
Sent: Monday, December 16, 2002 11:20 PM
Subject: Re: [olug] Argh!


> And that would achieve?
>
> Brian Roberson wrote:
>
> >one word...
> >
> >ulimit
> >
> >
> >
> >
> >----- Original Message -----
> >From: "Sam Tetherow" <tetherow at nol.org>
> >To: <olug at olug.org>
> >Sent: Sunday, December 15, 2002 11:24 PM
> >Subject: Re: [olug] Argh!
> >
> >
> >
> >
> >>You would have to check the source code for mozilla or gtfp but I would
> >>bet what the author does is open the file for writing when they go to
> >>save which will cause the file to be wiped.
> >>
> >>As for full memory and swap, many things write to log files or syslog
> >>and most programmers do not take the time to handle this gracefully.
> >> When say your /var partition fills up and syslog can no longer write to
> >>file the os will buffer the writes in memory in the vain hope that some
> >>disk space free up, when this doesn't occur, memory fills up, then swap
> >>space, once swap is full the writes start failing, as well as any new
> >>memory allocation.  Most programmers do not take the time to gracefully
> >>handle a failed alloc beyond printf(stderr, "cannot allocation
> >>memory\n"); exit;  But even those that do what is the proper behavior?
> >> How will apache serve a file if it cannot allocate the memory to read
> >>the file?    How is mysql suppose to handle a request if it cannot
> >>malloc memory for the temporary buffers it needs to build the results
set?
> >>
> >>
> >>
>
>
>
> _______________________________________________
> OLUG mailing list
> OLUG at olug.org
> http://lists.olug.org/mailman/listinfo/olug
>