For instance, it appears that select will return that a socket is
writable when there is, say 8k of buffer space in it. However, if
I'm sending 32k UDP packets, this still causes me to drop packets
due to a lack of resources...
Is there any IOCTL that can tell select how much space to require
before it thinks a socket is writable?
Many thanks,
Ben
--
Ben Greear <[email protected]> <Ben_Greear AT excite.com>
President of Candela Technologies Inc http://www.candelatech.com
ScryMUD: http://scry.wanfear.com http://scry.wanfear.com/~greear
* Ben Greear ([email protected]) wrote:
> For instance, it appears that select will return that a socket is
> writable when there is, say 8k of buffer space in it. However, if
> I'm sending 32k UDP packets, this still causes me to drop packets
> due to a lack of resources...
udp has a fixed 8k max payload. did you try breaking up your packets?
cheers,
-chris
>
> * Ben Greear ([email protected]) wrote:
> > For instance, it appears that select will return that a socket is
> > writable when there is, say 8k of buffer space in it. However, if
> > I'm sending 32k UDP packets, this still causes me to drop packets
> > due to a lack of resources...
>
> udp has a fixed 8k max payload. did you try breaking up your packets?
UDP has a 64K - headers max payload.
Alan Cox wrote:
>>* Ben Greear ([email protected]) wrote:
>>
>>>For instance, it appears that select will return that a socket is
>>>writable when there is, say 8k of buffer space in it. However, if
>>>I'm sending 32k UDP packets, this still causes me to drop packets
>>>due to a lack of resources...
>>>
>>udp has a fixed 8k max payload. did you try breaking up your packets?
>>
>
> UDP has a 64K - headers max payload.
Yes, and I am writing code to specifically try out large UDP
packet sizes, so limiting myself to a certain size is not at
all useful in this case....
Thanks,
Ben
--
Ben Greear <[email protected]> <Ben_Greear AT excite.com>
President of Candela Technologies Inc http://www.candelatech.com
ScryMUD: http://scry.wanfear.com http://scry.wanfear.com/~greear
Chris Wright wrote:
>
> * Ben Greear ([email protected]) wrote:
> > For instance, it appears that select will return that a socket is
> > writable when there is, say 8k of buffer space in it. However, if
> > I'm sending 32k UDP packets, this still causes me to drop packets
> > due to a lack of resources...
>
> udp has a fixed 8k max payload. did you try breaking up your packets?
Are you sure about that? UDP has a 16-bit field for the length. Thus the
standard technically allows for packet sizes (including header) of up to 2^16
(roughly 65K) bytes.
Chris
--
Chris Friesen | MailStop: 043/33/F10
Nortel Networks | work: (613) 765-0557
3500 Carling Avenue | fax: (613) 765-2986
Nepean, ON K2H 8E9 Canada | email: [email protected]
* Christopher Friesen ([email protected]) wrote:
> Chris Wright wrote:
> >
> > * Ben Greear ([email protected]) wrote:
> > > For instance, it appears that select will return that a socket is
> > > writable when there is, say 8k of buffer space in it. However, if
> > > I'm sending 32k UDP packets, this still causes me to drop packets
> > > due to a lack of resources...
> >
> > udp has a fixed 8k max payload. did you try breaking up your packets?
>
> Are you sure about that? UDP has a 16-bit field for the length. Thus the
> standard technically allows for packet sizes (including header) of up to 2^16
> (roughly 65K) bytes.
no, you are absolutely right, it's 16 bits. sorry for spewing
misinformation.
cheers,
-chris