On Wed, Oct 29, 2008 at 10:27 AM, Scott James Remnant <[EMAIL PROTECTED]> wrote: > On Wed, 2008-10-29 at 09:57 -0700, Garrett Cooper wrote: > >> On Wed, Oct 29, 2008 at 2:37 AM, Scott James Remnant <[EMAIL PROTECTED]> >> wrote: >> > On Tue, 2008-10-28 at 17:32 -0700, Garrett Cooper wrote: >> > >> >> After executing this example multiple times (~10 does the trick), I've >> >> gotten init + libdbus to become unresponsive to a large degree, where >> >> it starts printing out "latency error messages". I've seen this occur >> >> on QEMU/ppc and I haven't been able to replicate the issue on MIPS >> >> (yet). I have however seen the same error message when jamming a lot >> >> of DBUS requests to upstart using our in-house client. >> >> >> > The author string isn't transmitted across libdbus, so I'm not sure >> > that's relevant here? >> > >> > You're repeatedly allocating a 300KB author string? That'll be simply >> > thrashing memory? >> > >> But it's allocating memory and waiting for a reply from the dbus shmem >> bindings though -- that's where the issue can be seen. >> > The only communication with the bus daemon would be the signal > announcing the change of object; this doesn't include author > information. > >> As I said, I haven't been able to get the issue to pop up on a real >> target, but the performance issue pops up with single proc versions of >> emulators -- where time + memory is more constrained than conventional >> systems. So, I'm sure I could get the issue to pop up on a real target >> by raising the value size to an artificially large value, but >> shouldn't upstart be capping the amount of data it's passing through >> with its parser via strn* or strl*? >> > No, I vaguely believe the only sensible limits are 0, 1 and unlimited. > > If you don't have the memory to waste on things like author names, don't > put them in job files. > > Scott
I'm not so much worried about myself -- I'm worried about users implementing jobfiles without understanding the implications and malicious users. I test boundary conditions for a reason ;). -Garrett -- upstart-devel mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/upstart-devel
