Обсуждение: gdb with postgres
Hi,
--
Best Regards
Huang Qi Victor
I was using gdb to debug postgres. In order to debug the backend of running query, I start postgres first and use "select * from pg_backend_pid()" to ask for backend pid. Then I start gdb in another bash window with "gdb postgres" and attach the pid obtained above and set the breakpoint. Then I run the query from the first window. However, the debugging precess which is shown below is not going to the breakpoint. I tried many different breakpoints, but it always start from the 305 client_read_ended().
GNU gdb 6.6
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "sparc-sun-solaris2.10"...
(gdb) b qp_add_paths_to_joinrel
Breakpoint 1 at 0x1a6744: file joinpath.c, line 67.
(gdb) attach 23903
Attaching to program `/usrlocal/pgsql/bin/postgres', process 23903
Retry #1:
Retry #2:
Retry #3:
Retry #4:
[New LWP 1]
0xff0cbaa4 in _rt_boot () from /usr/lib/ld.so.1
(gdb) n
Single stepping until exit from function _rt_boot,
which has no line number information.
secure_read (port=0x4a7760, ptr=0x455948, len=8192) at be-secure.c:305
305 client_read_ended();
(gdb) n
pq_recvbuf () at pqcomm.c:767
767 if (r < 0)
(gdb) n
769 if (errno == EINTR)
(gdb) n
782 if (r == 0)
(gdb) n
788 return EOF;
(gdb) n
791 PqRecvLength += r;
(gdb)
Any one know what is going wrong? BTW, as you can see, the system is solaris.
--
Best Regards
Huang Qi Victor
On Mon, Jun 6, 2011 at 1:13 PM, HuangQi <huangqiyx@gmail.com> wrote: > Hi, > I was using gdb to debug postgres. In order to debug the backend of > running query, I start postgres first and use "select * from > pg_backend_pid()" to ask for backend pid. Then I start gdb in another bash > window with "gdb postgres" and attach the pid obtained above and set the > breakpoint. Then I run the query from the first window. However, the > debugging precess which is shown below is not going to the breakpoint. I > tried many different breakpoints, but it always start from the 305 > client_read_ended(). > Please compile with -O0 -g flags to see all the debug symbols. CFLAGS="-O0 -g" ./configure --enable-debug Thanks, Pavan -- Pavan Deolasee EnterpriseDB http://www.enterprisedb.com
Sorry, but recompile with this flag still doesn't work. <br /><br /><div class="gmail_quote">On 6 June 2011 15:46, PavanDeolasee <span dir="ltr"><<a href="mailto:pavan.deolasee@gmail.com">pavan.deolasee@gmail.com</a>></span> wrote:<br/><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div class="im">OnMon, Jun 6, 2011 at 1:13 PM, HuangQi <<a href="mailto:huangqiyx@gmail.com">huangqiyx@gmail.com</a>> wrote:<br/> > Hi,<br /> > I was using gdb to debug postgres. In order to debug the backend of<br /> > runningquery, I start postgres first and use "select * from<br /> > pg_backend_pid()" to ask for backend pid. Then I startgdb in another bash<br /> > window with "gdb postgres" and attach the pid obtained above and set the<br /> > breakpoint.Then I run the query from the first window. However, the<br /> > debugging precess which is shown below isnot going to the breakpoint. I<br /> > tried many different breakpoints, but it always start from the 305<br />> client_read_ended().<br /> ><br /><br /></div>Please compile with -O0 -g flags to see all the debug symbols.<br/><br /> CFLAGS="-O0 -g" ./configure --enable-debug<br /><br /> Thanks,<br /> Pavan<br /><font color="#888888"><br/> --<br /> Pavan Deolasee<br /> EnterpriseDB <a href="http://www.enterprisedb.com" target="_blank">http://www.enterprisedb.com</a><br/></font></blockquote></div><br /><br clear="all" /><br />-- <br />BestRegards<br />Huang Qi Victor<br />
On Mon, Jun 6, 2011 at 3:43 AM, HuangQi <huangqiyx@gmail.com> wrote: > Hi, > I was using gdb to debug postgres. In order to debug the backend of > running query, I start postgres first and use "select * from > pg_backend_pid()" to ask for backend pid. Then I start gdb in another bash > window with "gdb postgres" and attach the pid obtained above and set the > breakpoint. Then I run the query from the first window. However, the > debugging precess which is shown below is not going to the breakpoint. I > tried many different breakpoints, but it always start from the 305 > client_read_ended(). > > GNU gdb 6.6 > Copyright (C) 2006 Free Software Foundation, Inc. > GDB is free software, covered by the GNU General Public License, and you are > welcome to change it and/or distribute copies of it under certain > conditions. > Type "show copying" to see the conditions. > There is absolutely no warranty for GDB. Type "show warranty" for details. > This GDB was configured as "sparc-sun-solaris2.10"... > (gdb) b qp_add_paths_to_joinrel > Breakpoint 1 at 0x1a6744: file joinpath.c, line 67. > (gdb) attach 23903 > Attaching to program `/usrlocal/pgsql/bin/postgres', process 23903 > Retry #1: > Retry #2: > Retry #3: > Retry #4: > [New LWP 1] > 0xff0cbaa4 in _rt_boot () from /usr/lib/ld.so.1 > (gdb) n > Single stepping until exit from function _rt_boot, > which has no line number information. > secure_read (port=0x4a7760, ptr=0x455948, len=8192) at be-secure.c:305 > 305 client_read_ended(); > (gdb) n > pq_recvbuf () at pqcomm.c:767 > 767 if (r < 0) > (gdb) n > 769 if (errno == EINTR) > (gdb) n > 782 if (r == 0) > (gdb) n > 788 return EOF; > (gdb) n > 791 PqRecvLength += r; > (gdb) > Any one know what is going wrong? BTW, as you can see, the system is > solaris. Perhaps you want "c" for "continue" rather than "n" for "next". -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
If I enter c, gdb will directly finish executing this process and current query will finish. Furthermore, if I enter next query, gdb will not debug it and stay in continue status.
--
Best Regards
Huang Qi Victor
On 6 June 2011 21:44, Robert Haas <robertmhaas@gmail.com> wrote:
Perhaps you want "c" for "continue" rather than "n" for "next".On Mon, Jun 6, 2011 at 3:43 AM, HuangQi <huangqiyx@gmail.com> wrote:
> Hi,
> I was using gdb to debug postgres. In order to debug the backend of
> running query, I start postgres first and use "select * from
> pg_backend_pid()" to ask for backend pid. Then I start gdb in another bash
> window with "gdb postgres" and attach the pid obtained above and set the
> breakpoint. Then I run the query from the first window. However, the
> debugging precess which is shown below is not going to the breakpoint. I
> tried many different breakpoints, but it always start from the 305
> client_read_ended().
>
> GNU gdb 6.6
> Copyright (C) 2006 Free Software Foundation, Inc.
> GDB is free software, covered by the GNU General Public License, and you are
> welcome to change it and/or distribute copies of it under certain
> conditions.
> Type "show copying" to see the conditions.
> There is absolutely no warranty for GDB. Type "show warranty" for details.
> This GDB was configured as "sparc-sun-solaris2.10"...
> (gdb) b qp_add_paths_to_joinrel
> Breakpoint 1 at 0x1a6744: file joinpath.c, line 67.
> (gdb) attach 23903
> Attaching to program `/usrlocal/pgsql/bin/postgres', process 23903
> Retry #1:
> Retry #2:
> Retry #3:
> Retry #4:
> [New LWP 1]
> 0xff0cbaa4 in _rt_boot () from /usr/lib/ld.so.1
> (gdb) n
> Single stepping until exit from function _rt_boot,
> which has no line number information.
> secure_read (port=0x4a7760, ptr=0x455948, len=8192) at be-secure.c:305
> 305 client_read_ended();
> (gdb) n
> pq_recvbuf () at pqcomm.c:767
> 767 if (r < 0)
> (gdb) n
> 769 if (errno == EINTR)
> (gdb) n
> 782 if (r == 0)
> (gdb) n
> 788 return EOF;
> (gdb) n
> 791 PqRecvLength += r;
> (gdb)
> Any one know what is going wrong? BTW, as you can see, the system is
> solaris.
--
Robert HaasEnterpriseDB: http://www.enterprisedb.comThe Enterprise PostgreSQL Company
--
Best Regards
Huang Qi Victor
On Mon, Jun 6, 2011 at 9:47 AM, HuangQi <huangqiyx@gmail.com> wrote: > If I enter c, gdb will directly finish executing this process and current > query will finish. Furthermore, if I enter next query, gdb will not debug it > and stay in continue status. Hmm, that must mean your breakpoint isn't properly set. Instead of doing gdb postgres and then using attach, try just doing gdb -p PIDNAME, then set your breakpoint, then continue. That's how I've always done it, anyway... -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
HuangQi <huangqiyx@gmail.com> wrote: >>> (gdb) b qp_add_paths_to_joinrel >>> Breakpoint 1 at 0x1a6744: file joinpath.c, line 67. >>> (gdb) attach 23903 > If I enter c, gdb will directly finish executing this process and > current query will finish. Are you absolutely sure that running your query will result in a call to this function? -Kevin
<div class="gmail_quote">On 6 June 2011 21:57, Kevin Grittner <span dir="ltr"><<a href="mailto:Kevin.Grittner@wicourts.gov">Kevin.Grittner@wicourts.gov</a>></span>wrote:<br /><blockquote class="gmail_quote"style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><divclass="im">HuangQi <<a href="mailto:huangqiyx@gmail.com">huangqiyx@gmail.com</a>> wrote:<br /><br /></div><divclass="im">>>> (gdb) b qp_add_paths_to_joinrel<br /> >>> Breakpoint 1 at 0x1a6744: file joinpath.c,line 67.<br /> >>> (gdb) attach 23903<br /><br /></div><div class="im">> If I enter c, gdb will directlyfinish executing this process and<br /> > current query will finish.<br /><br /></div>Are you absolutely surethat running your query will result in a<br /> call to this function?<br /><font color="#888888"><br /> -Kevin<br /></font></blockquote></div><br/><br />Thanks guys for your idea. I found the solution. Because after made some change inpostgres and make them, I didn't stop the server first. Now I stop it and start after reinstall, then using gdb is justfine. Thanks for your ideas.<br clear="all" /><br />-- <br />Best Regards<br />Huang Qi Victor<br />