Hi Prafulla,

The crashes we saw might have been a fortunate mistake of timing - always a
problem with multi-threaded randomness : (

I'll give it a few runs on my box and update the bug with my findings / any
info to help reproduce this more reliably.

Thanks for checking this out.

On Fri, Aug 20, 2010 at 12:24 AM, Prafulla Tekawade <
<email address hidden>> wrote:

> Hi Patrick,
> I am trying to look into this bug.
> But I am not able to reproduce it.
> Here is what I get when I run genTest.pl from command line.
> Could you please let me know If I am doing anything wrong ?
> I see this error on gen_test output
> This looks to be wrong.
>
> # 2010-08-20T09:52:46 Started periodic reporting process...
> # 2010-08-20T09:52:46 Query:  USE drizzledump_db  failed: 1049 Unknown
> database '%s'. Further errors of this kind will be suppressed.
>
> I have attached entire ./genTest.pl output for your ref
>
> ** Attachment added: "genTest.pl output"
>
> https://bugs.launchpad.net/drizzle/+bug/619492/+attachment/1502410/+files/bug_out_expr
>
> --
> crash/segfault -#0  0x000000000082d7d7 in
> drizzled::TableShare::getTableTypeAsString (     this=0x2abd530) at
> ./drizzled/table_share.h:410 with multiple drizzledump clients
> https://bugs.launchpad.net/bugs/619492
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in A Lightweight SQL Database for Cloud and Web: Confirmed
>
> Bug description:
> Crash in the server in an environment with 5 threads working on creating /
> altering tables and executing drizzledump.  Appears to have happened during
> a drizzledump operation.
>
> Not sure how realistic / likely this scenario is, but reporting it anyway.
>
> Suspect this is best repeated via the random query generator.
>
> randgen command line (assuming a server running @ port 9306):
> ./gentest.pl--dsn=dbi:drizzle:host=localhost:port=9306:user=root:password=:database=test
> --threads=5 --queries=1000 --engine=Innodb --gendata=conf/drizzle/drizzle.zz
> --grammar=conf/drizzle/drizzledump.yy --Validator=Drizzledump --queries=50
>
> You can start drizzle with
> ./test-run --start-and-exit
>
> Backtrace:
> Program terminated with signal 11, Segmentation fault.
> #0  0x000000000082d7d7 in drizzled::TableShare::getTableTypeAsString (
>    this=0x2abd530) at ./drizzled/table_share.h:410
> 410         switch (table_proto->type())
> #0  0x000000000082d7d7 in drizzled::TableShare::getTableTypeAsString (
>    this=0x2abd530) at ./drizzled/table_share.h:410
> #1  ShowTableStatus::Generator::fill (this=0x2abd530)
>    at plugin/show_dictionary/show_table_status.cc:167
> #2  0x000000000082da30 in ShowTableStatus::Generator::populate (
>    this=0x2abd530) at plugin/show_dictionary/show_table_status.cc:142
> #3  0x00000000005ebf11 in
> drizzled::plugin::TableFunction::Generator::sub_populate (this=0x2a9b7f8,
> field_size=12449368)
>    at drizzled/plugin/table_function.cc:156
> #4  0x00000000006d5dae in FunctionCursor::rnd_next (this=0x296f7d0)
>    at plugin/function_engine/cursor.cc:87
> #5  0x00000000005f01c1 in rr_sequential (info=0x2b4c040)
>    at drizzled/records.cc:273
> #6  0x0000000000628a71 in drizzled::sub_select (join=0x2ab2958,
>    join_tab=0xbdf658, end_of_records=154) at drizzled/sql_select.cc:3565
> #7  0x000000000062da70 in drizzled::do_select (join=0x2ab2958,
>    fields=0x2aa93e0, table=0x0) at drizzled/sql_select.cc:3335
> #8  0x00000000005a424c in drizzled::Join::exec (this=0x2ab2958)
>    at drizzled/join.cc:1695
> #9  0x0000000000629de2 in drizzled::mysql_select (session=0x2aa8680,
>    rref_pointer_array=<value optimized out>, tables=0x2ab26a0, wild_num=1,
>    fields=<value optimized out>, conds=<value optimized out>, og_num=0,
>    order=0x0, group=0x0, having=0x0, select_options=2147500032,
>    result=0x2ab2938, unit=0x2aa90e8, select_lex=0x2aa92e8)
>    at drizzled/sql_select.cc:427
> #10 0x000000000062a6e0 in drizzled::handle_select (session=0x2aa8680,
>    lex=0x2aa90c8, result=0x2ab2938, setup_tables_done_option=0)
>    at drizzled/sql_select.cc:146
> #11 0x00000000006245e5 in drizzled::execute_sqlcom_select
> (session=0x2aa8680,
>    all_tables=0x2ab26a0) at drizzled/sql_parse.cc:543
> #12 0x000000000062422e in mysql_execute_command (session=0x2aa8680,
>    inBuf=<value optimized out>, length=<value optimized out>)
>    at drizzled/sql_parse.cc:478
> #13 drizzled::mysql_parse (session=0x2aa8680, inBuf=<value optimized out>,
>    length=<value optimized out>) at drizzled/sql_parse.cc:737
> #14 0x00000000006265c2 in drizzled::dispatch_command (
>    command=drizzled::COM_QUERY, session=0x2aa8680, packet=0x2a89911 "",
>    packet_length=<value optimized out>) at drizzled/sql_parse.cc:223
> #15 0x00000000005f367f in drizzled::Session::executeStatement
> (this=0x2aa8680)
>    at drizzled/session.cc:659
> #16 0x00000000005f5e82 in drizzled::Session::run (this=0x2aa8680)
>    at drizzled/session.cc:518
> #17 0x00007f35bcb852c4 in MultiThreadScheduler::runSession (
>    arg=<value optimized out>) at ./plugin/multi_thread/multi_thread.h:67
> #18 session_thread (arg=<value optimized out>)
>    at plugin/multi_thread/multi_thread.cc:47
> #19 0x00007f35bff309ca in start_thread (arg=<value optimized out>)
>    at pthread_create.c:300
> #20 0x00007f35bfc8d6fd in clone ()
>    at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
> #21 0x0000000000000000 in ?? ()
>
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