How to increase Max. limit of Fifo size on Linux?

Hi,

Does anybody know how to increase FIFO Max. size limit on RedHat 9.0?
My current limit is 8*512 bytes, which is as shown by "ulimit -p" command.
I tried to increase it to 20*512 bytes using command: "ulimit -p 20".
Got this error:

ulimit: pipe size: cannot modify limit: Invalid argument

Let me know is there is any other way to change the Max. size of Fifo/Pipe?

TIA,
Sandeep

Sandeep wrote:

> Hi,
>
> Does anybody know how to increase FIFO Max. size limit on RedHat 9.0?
> My current limit is 8*512 bytes, which is as shown by "ulimit -p" command.
> I tried to increase it to 20*512 bytes using command: "ulimit -p 20".
> Got this error:
>
> ulimit: pipe size: cannot modify limit: Invalid argument
>
> Let me know is there is any other way to change the Max. size of Fifo/Pipe?

I believe that, in order to increase the size of the PIPE allocation, you
are going to have to change some kernel constants and recompile your kernel.

/usr/include/linux/pipe_fs_i.h carries a constant called
PIPE_SIZE
which defines the size of a pipe. You will have to increase this value, and
recompile the linux/fs/pipe.c (at least) support. I don't know what other
downstream effects this will have; you may have to make other changes to the
kernel or apps and recompile as well.

--
Lew Pitcher, IT Consultant, Application Architecture
Enterprise Technology Solutions, TD Bank Financial Group

(Opinions expressed here are my own, not my employer's)