What does sendfile_max_chunk do?

Hello,

Once again I am in need of your help!
I’m looking to document directives that are missing from the Wiki.
I found loads in the source code, especially thanks to Manlio P…

I’ve stumbled upon “sendfile_max_chunk” declared in
ngx_http_core_module.c.
I investigated what this does, here is what I found:

  • it’s a size value directive
  • it’s set to 0 by default (presumably this means no maximum size)

I’m not sure what it does.
It is probably somewhat connected to the use of sendfile, my
understanding is as follows:
“This directive defines the maximum size of chunks to be read from the
storage system when using sendfile”.
Is this a correct and accurate definition? Could anyone provide more
information?

Thanks a lot in advance for helping me clear it out!

Best regards,
Costello

Posted at Nginx Forum:

On Fri, May 14, 2010 at 06:52:29AM -0400, Costello wrote:

I’m not sure what it does.
It is probably somewhat connected to the use of sendfile, my understanding is as follows:
“This directive defines the maximum size of chunks to be read from the storage system when using sendfile”.
Is this a correct and accurate definition? Could anyone provide more information?

On fast local connection sendfile() in Linux may send tens of megabytes
per one syscall blocking other connections. sendfile_max_chunk allows
to limit the maximum size per one sendfile() operation.


Igor S.
http://sysoev.ru/en/