Re: Write Ahead Logging for Hash Indexes

Hi All,

I am getting following error when running the test script shared by
Jeff -[1] . The error is observed upon executing the test script for
around 3-4 hrs.

57869 INSERT XX000 2016-09-14 07:58:01.211 IST:ERROR:  lock
buffer_content 1 is not held
57869 INSERT XX000 2016-09-14 07:58:01.211 IST:STATEMENT:  insert into
foo (index) select $1 from generate_series(1,10000)

124388 INSERT XX000 2016-09-14 11:24:13.593 IST:ERROR:  lock
buffer_content 10 is not held
124388 INSERT XX000 2016-09-14 11:24:13.593 IST:STATEMENT:  insert
into foo (index) select $1 from generate_series(1,10000)

124381 INSERT XX000 2016-09-14 11:24:13.594 IST:ERROR:  lock
buffer_content 10 is not held
124381 INSERT XX000 2016-09-14 11:24:13.594 IST:STATEMENT:  insert
into foo (index) select $1 from generate_series(1,10000)

[1]- https://www.postgresql.org/message-id/CAMkU%3D1xRt8jBBB7g_7K41W00%3Dbr9UrxMVn_rhWhKPLaHfEdM5A%40mail.gmail.com

Please note that i am performing the test on latest patch for
concurrent hash index and WAL log in hash index shared by Amit
yesterday.


With Regards,
Ashutosh Sharma
EnterpriseDB: http://www.enterprisedb.com



On Wed, Sep 14, 2016 at 12:04 AM, Jesper Pedersen
<jesper.pedersen@redhat.com> wrote:
> On 09/13/2016 07:41 AM, Amit Kapila wrote:
>>>
>>> README:
>>> +in_complete split flag.  The reader algorithm works correctly, as it
>>> will
>>> scan
>>>
>>> What flag ?
>>>
>>
>> in-complete-split flag which indicates that split has to be finished
>> for that particular bucket.  The value of these flags are
>> LH_BUCKET_NEW_PAGE_SPLIT and LH_BUCKET_OLD_PAGE_SPLIT for new and old
>> bucket respectively.  It is set in hasho_flag in special area of page.
>> I have slightly expanded the definition in README, but not sure if it
>> is good idea to mention flags defined in hash.h. Let me know, if still
>> it is unclear or you want some thing additional to be added in README.
>>
>
> I think it is better now.
>
>>> hashxlog.c:
>>>
>>> hash_xlog_move_page_contents
>>> hash_xlog_squeeze_page
>>>
>>> Both have "bukcetbuf" (-> "bucketbuf"), and
>>>
>>> +               if (BufferIsValid(bukcetbuf));
>>>
>>> ->
>>>
>>> +               if (BufferIsValid(bucketbuf))
>>>
>>> and indent following line:
>>>
>>> LockBufferForCleanup(bukcetbuf);
>>>
>>> hash_xlog_delete
>>>
>>> has the "if" issue too.
>>>
>>
>> Fixed all the above cosmetic issues.
>>
>
> I meant there is an extra ';' on the "if" statements:
>
> +               if (BufferIsValid(bukcetbuf)); <--
>
> in hash_xlog_move_page_contents, hash_xlog_squeeze_page and
> hash_xlog_delete.
>
>
> Best regards,
>  Jesper
>
>
>
>
>
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