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Date: Sun, 03 Jan 2010 23:44:00 -0000
From: Guillaume Yziquel <guillaume.yziquel@citycable.ch>
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To: Jan Kratochvil <jan.kratochvil@redhat.com>
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Subject: Re: watchpoint hangs.
References: <4B3FB2BC.9040104@citycable.ch> <20100102205938.GA9421@host0.dyn.jankratochvil.net>
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Jan Kratochvil a =C3=A9crit :
> On Sat, 02 Jan 2010 21:55:24 +0100, Guillaume Yziquel wrote:
>
>>> (gdb) print box
>>> $1 =3D {0x0 <repeats 64 times>}
>>> (gdb) watch box
>>> Watchpoint 2: box
>>> (gdb) continue
>>> Continuing.
>>
>> And it eats up 90% of one of my CPU from now on...
>=20
> As it printed "Watchpoint" and not "Hardware watchpoint" it means it had =
to
> use software watchpoint for some reason.  Therefore it needs to singleste=
p the
> code which should work but it is very very slow.
>=20
> On amd64 (x86_64) there are only 4 hardware watch registers with 8 bytes =
range
> each, that is 32 bytes of maximum hardware-watchable bytes of memory.
>=20
> According to "{0x0 <repeats 64 times>}" your requested memory range is
> probably larger.
>=20
> Try to reduce the watched memory range in your specific debugging case.
>=20
> Regards,
> Jan

Thank you so much. This has helped tremendously. Symbol collision issue=20
detected and solved.

By the way, completely off-topic: moving to git is indeed a very very=20
worthwile solution. It takes quite some pain at the beginning, but it's=20
totally worth it.

--=20
      Guillaume Yziquel
http://yziquel.homelinux.org/