Problem with daemonize

Server Mongrel
1

Hi,

I am new to working with mongrel (and rails in general) and I am
experiencing a problem with mongrel. I have a rails application that
for one view parses some information from our SVN server. I have to
call the SVN several times to get all the information I need and it
takes about 30 sec. to complete the request (This is ok because it is an
internal app). The problem is that this only works when I run mongrel
non daemonized. If I deamonize the process the rest of my rails site
works fine. But, this page hangs when I try to load it. I have looked
through the mongrel.log, error.log, and development.log (still using the
development environment) and I cannot find any errors. The web browser
(firefox 3) just sits there and acts like it loads the page but nothing
happens. Does anybody know what might be the problem? It seams weird
to me that it works when non deamonized but does not work when mongrel
is run as a deamon.

Thanks for any ideas.

Josh

2

“Josh” == Josh M. [email protected] writes:
Josh> happens. Does anybody know what might be the problem? It
seams weird
Josh> to me that it works when non deamonized but does not work when
mongrel
Josh> is run as a deamon.

When daemonized, does it run as you, or as another user?
When it hangs, do you see “svn” processes waiting in the ps listing?
Do you get errors from the popen calls that you are doing?
Do you get anything when you look at the page source for the page that
loads?

–
Michael R. [email protected]
Director – Consumer Desktop Development, Simtone Corporation, Ottawa,
Canada
Personal: Michael Richardson's Directory

SIMtone Corporation fundamentally transforms computing into simple,
secure, and very low-cost network-provisioned services pervasively
accessible by everyone. Learn more at www.simtone.net and
www.SIMtoneVDU.com

3

When daemonized, does it run as you, or as another user?
The deamonized process runs as me.

When it hangs, do you see “svn” processes waiting in the ps listing?
There is no svn process in the ps listing (“ps afx | grep svn”)

Do you get errors from the popen calls that you are doing?
It actually hangs on the call and I do not get any output.

Do you get anything when you look at the page source for the page that
loads?
I get this “”

Thanks,

Josh

unknown wrote:

“Josh” == Josh M. [email protected] writes:
Josh> happens. Does anybody know what might be the problem? It
seams weird
Josh> to me that it works when non deamonized but does not work when
mongrel
Josh> is run as a deamon.

When daemonized, does it run as you, or as another user?
When it hangs, do you see “svn” processes waiting in the ps listing?
Do you get errors from the popen calls that you are doing?
Do you get anything when you look at the page source for the page that
loads?

–
Michael R. [email protected]
Director – Consumer Desktop Development, Simtone Corporation, Ottawa,
Canada
Personal: Michael Richardson's Directory

SIMtone Corporation fundamentally transforms computing into simple,
secure, and very low-cost network-provisioned services pervasively
accessible by everyone. Learn more at www.simtone.net and
www.SIMtoneVDU.com

4

“Josh” == Josh M. [email protected] writes:
When daemonized, does it run as you, or as another user?
Josh> The deamonized process runs as me.

>> When it hangs, do you see "svn" processes waiting in the ps

listing?
Josh> There is no svn process in the ps listing (“ps afx | grep
svn”)

>> Do you get errors from the popen calls that you are doing?
Josh> It actually hangs on the call and I do not get any output.

I would run “strace -f -p XXXX” on the mongrel process(es), and try
things. I would suspect either that the exec part of the popen() fails
due to $PATH issues. Since there is no “svn” process around, then it
should not be an issue with the underlying ssh that might be invoked.
You might also replace the call to svn with echo/cat/env.

instead of:
foo = IO.popen(“svn stuff”, “r”)

do:
foo = IO.popen(“sh -c ‘env >/tmp/env$$; cat /tmp/canned-svn-reply’”,
“r”)

and if that helps diag things.

–
Michael R. [email protected]
Director – Consumer Desktop Development, Simtone Corporation, Ottawa,
Canada
Personal: Michael Richardson's Directory

SIMtone Corporation fundamentally transforms computing into simple,
secure, and very low-cost network-provisioned services pervasively
accessible by everyone. Learn more at www.simtone.net and
www.SIMtoneVDU.com

5

Hi,

Sorry it took so long have been called way to other projects. Now that
I am back I have been doing some looking and it seams whenever I try to
access the file system (even to run an ‘ls’ or ‘pwd’ command) it spawns
another mongrel and hangs. The last line in the strace log:

20558 select(4, [3], [2], [], {0, 871586}) = -1 EBADF (Bad file
descriptor)

This line prints a huge number of times in a very very short period of
time (I shortend the log so that it would be smaller. But it printed
this line in the order of 100,000 times in a couple of minutes). Even
when I run as the root user this same thing happens.

I have attached the strace log because I have looked at it but cannot
really make heads or tails of what it means. Thanks, for all ideas.

Josh

P.S. Sorry, the strace file is about 400k and is to big to attach. If
anybody is willing to look at it please just email me
[email protected] and I will be happy to send it to you.

unknown wrote:

“Josh” == Josh M. [email protected] writes:
When daemonized, does it run as you, or as another user?
Josh> The deamonized process runs as me.

>> When it hangs, do you see "svn" processes waiting in the ps

listing?
Josh> There is no svn process in the ps listing (“ps afx | grep
svn”)

>> Do you get errors from the popen calls that you are doing?
Josh> It actually hangs on the call and I do not get any output.

I would run “strace -f -p XXXX” on the mongrel process(es), and try
things. I would suspect either that the exec part of the popen() fails
due to $PATH issues. Since there is no “svn” process around, then it
should not be an issue with the underlying ssh that might be invoked.
You might also replace the call to svn with echo/cat/env.

instead of:
foo = IO.popen(“svn stuff”, “r”)

do:
foo = IO.popen(“sh -c ‘env >/tmp/env$$; cat /tmp/canned-svn-reply’”,
“r”)

and if that helps diag things.

–
Michael R. [email protected]
Director – Consumer Desktop Development, Simtone Corporation, Ottawa,
Canada
Personal: Michael Richardson's Directory

SIMtone Corporation fundamentally transforms computing into simple,
secure, and very low-cost network-provisioned services pervasively
accessible by everyone. Learn more at www.simtone.net and
www.SIMtoneVDU.com