Re: Bug #39574 Falcon asserts after restart in DataPage.cpp line 87

[Hakan Kuecuekyilmaz]

On Do, 2008-09-25 at 23:56 -0500, Kevin Lewis wrote:
> Hakan,
> 
> It sounded like you wanted to try to figure this one out.  Do you want 
> me to assign it to you?  Or has it become too time consuming?
> 
> If you can repeat this, you might want to try this;
> 
> DataPage.h, line 37;
> 
> struct LineIndex {
> -	short	offset;
> -	short	length;	 // negative means record has overflow page
> +	uint16	offset;
> +	uint16	length;	 // negative means record has overflow page
> 	};
> 
> The offset value seems to be the problem in the assert.  Not sure if you 
> ever actually got it stopped in the debugger to see the value there. 
> But making this variable hold up to 65535 instead of 32767 may do the trick.

Yes, that was the problem. I was only able to reproduce this bug with
falcon_page_size of 32k in our mysql-6.0-falcon tree. But length should
be signed as the comment notes it. So I did this:

=== modified file 'storage/falcon/DataPage.h'
--- storage/falcon/DataPage.h   2008-06-17 17:41:54 +0000
+++ storage/falcon/DataPage.h   2008-09-27 05:37:14 +0000
@@ -35,8 +35,8 @@
 struct SectionAnalysis;

 struct LineIndex {
-       short   offset;
-       short   length; // negative means record has overflow page
+       uint16  offset;
+       int16   length; // negative means record has overflow page
        };

 class DataPage : public Page


I verified with a printf() just above the assertion and sometimes we got
above 32767

DataPage::updateRecord(): 32731 + 37 = 32768

However, after fixing this bug I hit other assertion(s)

sql/mysqld(Error::error(char const*, ...)+0xea)[0x8b7438]
sql/mysqld(Cache::fetchPage(Dbb*, int, PageType,
LockType)+0x2c1)[0x899a71]
sql/mysqld(Dbb::fetchPage(int, PageType, LockType)+0x24)[0x8af1c6]
sql/mysqld(Dbb::handoffPage(Bdb*, int, PageType,
LockType)+0x1f)[0x8af549]
sql/mysqld(Section::findNextRecord(int, int, Stream*)+0xec)[0x8ec4c4]
sql/mysqld(Section::findNextRecord(int, int, Stream*)+0x2ab)[0x8ec683]
sql/mysqld(Section::findNextRecord(int, Stream*)+0x16)[0x8ec6ec]
sql/mysqld(Dbb::findNextRecord(Section*, int, Stream*)+0x11)[0x8aea51]
sql/mysqld(TableSpaceManager::bootstrap(int)+0x30a)[0x8872ac]
sql/mysqld(Database::openDatabase(char const*)+0x25a)[0x8ab516]
sql/mysqld(Connection::getDatabase(char const*, char const*,
Threads*)+0x109)[0x8a132d]
sql/mysqld(Connection::openDatabase(char const*, char const*, char
const*, char const*, char const*, Threads*)+0x120)[0x8a28e2]
sql/mysqld(StorageDatabase::getOpenConnection()+0x63)[0x87214b]
sql/mysqld(StorageHandler::initialize()+0x83)[0x873f15]
sql/mysqld(StorageInterface::falcon_init(void*)+0x22a)[0x86c4fc]
sql/mysqld(ha_initialize_handlerton(st_plugin_int*)+0x7f)[0x766816]
sql/mysqld[0x7fcee7]
sql/mysqld(plugin_init(int*, char**, int)+0x88b)[0x7ff34c]
sql/mysqld[0x67247c]
sql/mysqld(main+0x35a)[0x672de3]
/lib/libc.so.6(__libc_start_main+0xe6)[0x7f1c5d37c1a6]
sql/mysqld(__gxx_personality_v0+0x269)[0x5b0729]
[Falcon] Error: page 102/0 wrong page type, expected 7 got 2


-- 
Hakan Küçükyılmaz, Senior Software Engineer DBTG/MySQL +49 160
98953296
Sun Microsystems GmbH     Sonnenallee 1, DE-85551 Kirchheim-Heimstetten
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