Experiment to test TCP keepalive for pop3d proxies
wes at umich.edu
Tue Jun 1 16:49:52 EDT 2010
On 01 Jun 2010, at 14:05, Gary Mills wrote:
> # pstack 12708
> 12708: pop3d -s
> feb1a5c5 read (0, 817faf0, b)
> fec2dfaf sock_read () + 3f
> I don't know why the stack trace is so short with these.
Thinking about this a little more...
sock_read() is probably from openssl's BIO layer, and the stack trace
is probably truncated because pstack can't follow the backtrace
through the function pointer that SSL_read() is using to access
sock_read(). This is an SSL connection, right? Take a look at the
SSL_read() man page, for an idea of what can go wrong. Having
written something very much like the prot suite for another project,
I can say that SSL is really much happier with non-blocking IO, if
you're hoping for control to return to the call at some point.
More information about the Info-cyrus