[CentOS] 5.5 & gspca

Fri Jun 11 21:10:51 UTC 2010
m.roth at 5-cent.us <m.roth at 5-cent.us>

John wrote:
> On Fri, 2010-06-11 at 16:15 -0400, m.roth at 5-cent.us wrote:
>> Irritating quirkyness: we have a bunch of videocams. To use, we use
>> gspca.
<snip>
>> so the first number is the packet #, which I see 0 through 3 or 5 in my
>> logs. The error, which is the status, *if* errno.h has any relation,
>> says that it's an EXDEV, which suggests that it's trying to hard link
>> across devices, which AFAIK it's not: the home directory for the user the
>> device runs is is automounted, and it gets created there.
>>
>> Anyone have any clues why, all of a sudden, the first few packets are
>> showing a status code? Could it be a timing issue?
> ---
> Well I find these things interesting.  Could very well be timing in the
> frame buffers/packets.  I'm guessing this is the newest latest kernel.
> I've seen somewhere this week somewhere on the web about a related
> issue.

Yep - just upgraded the other day.
>
> So guessing it works correctly on the previous kernel?  Just something

Yep.

> to ponder here is the machine really loaded heavily?  I ask because if

Nope. Low loads, as well, according to top.

> so the kernel can't function on "us" microsecond timing.  It becomes
> very critical when it comes to that nature.

Right - my manager actually encouraged me to look at the code, and I was
trying to recompile after putting a sleep(1) before any of the streaming
is called, but I'm having all kinds of grief, since it can't find
<unistd.h>, and when I put it in as #include "/usr/include/unistd.h", it
spits out a ton of undefineds, and unuseds, etc.
>
> Last thing is the timing routine function getting called in userspace or
> kernel?  I have had my share of day to day problems like this.  Last

Kernel. gspcs is a module, used by the motion daemon.

> thing was anything in /etc/sysctl.conf changed? Finally whats nice is,
> it could have been coded to skip a frame sequence where the before and
> after timing did not match and you eye would never see it..

Doesn't look like it - /etc/sysctl.conf is dated last Aug.

Thanks for the thoughts.

         mark