Re: [PATCH 0/2] Better handling of slow remote transfers

Gary Benson
2015-08-12T13:38:32Z

Pedro Alves wrote:
> On 08/12/2015 02:02 PM, Gary Benson wrote:
> >>>> > > > I was only OK with trying to make transfers interruptible in the
> >>>> > > > branch assuming it was something non-invasive, like a missing
> >>>> > > > QUIT here and there.
> >>> > >
> >>> > > No, gdbserver sends the data in PBUFSIZ chunks, but GDB reads the
> >>> > > data a character at a time.
> >> >
> >> > Can you expand on this? What code is it that reads the data a
> >> > character at a time? What data is gdb getting at when it does that?
> > I was looking in getpkt_or_notif_sane_1, but I think maybe I misread
> > it. I'll get back to you on this...
>
> That's the very low level of RSP packets, which as you noted will
> have a reasonable cap. It sounds to me there's a loop somewhere in
> a higher layer that is missing a QUIT. E.g., we have quits
> in dwarf2read.c which allow interrupting reading big binaries,
> even if locally. So what is the higher level operation that
> gdb is doing when you try to interrupt, but can't?

remote_hostio_pread. I'm trying to make remote_hostio_pread
interruptible. BFD is doing large remote_hostio_pread which
are resulting in large vFile:pread: packet responses.

Cheers,
Gary

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