Re: udp input queue

From: Casper H.S. Dik (Casper.Dik_at_Sun.COM)
Date: 11/25/03 

Date: 25 Nov 2003 13:21:26 GMT

clapidus@hotmail.com (Claudio Lapidus) writes:

>Hello

>I'm debugging an application than listens on an UDP (unprivileged)
>port and I'm suspecting a queue buildup at certain peak load times. I
>need to monitor the status of a particular input queue (how many
>packets/bytes are waiting for service) at a certain moment.

>I investigated netstat and ndd but haven't found anything useful. I recall
>being able to do this on Tru64's and Linux' versions of netstat, but
>on Solaris I'm stuck.

It's fairly tricky because you need to get at the "read queue" belonging
to the specific file descriptor.

The chain to follow is something like this:

(fd 30, in pid 0t2215)

0t2215::pid2proc | ::print proc_t p_user.u_finfo.fi_list[0t30].uf_file[0].f_vn
ode[0].v_stream[0].sd_wrq[-1]

(mdb doesn't understand the [-1] syntax, so you need to print the write
queue and then substract (sizeof queue_t); then dereference that
to get "q_count".

Casper 

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