Hi!

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"Sergei" == Sergei Golubchik writes:

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=== modified file 'sql/sql_base.cc' --- a/sql/sql_base.cc 2012-04-19 06:16:30 +0000 +++ b/sql/sql_base.cc 2012-05-09 18:59:45 +0000 @@ -933,7 +938,8 @@ for (uint idx=0 ; idx < open_cache.records ; idx++) { TABLE *table=(TABLE*) hash_element(&open_cache,idx); - if (table->in_use) + if (table->in_use && + (!set_readonly_mode || !table->file->has_transactions()))

Sergei> I wonder how this could work. The line below sets a flag *on a thread*. Sergei> The task description tells "not wait for transactional tables", while your Sergei> change means "not set a flag if all tables used in a thread are Sergei> transactional". That is, if a thread uses both transactional and Sergei> non-transactional tables, your change does nothing. I think this is actually correct. If a statement uses both transactional and non-transactional tables, the non transactional tables should be flushed as part of set readonly=1 The flag: table->in_use->some_tables_deleted is only use as a check if thr_lock() should fail. If you have a single non transactional table and the thread is doing a lock tables, we should close the table (and thus all the tables) and reopen it. However there is a couple of other things that needs to be done. If we are not going to increment the refresh version when doing set readonly, we should reset the refresh version for any non transactional open table to 0 to force it to be reopened. Holyfoot, how did you test this feature? Regards, Monty

Sergei, 11.05.2012 19:44, Sergei Golubchik wrote:

=== modified file 'mysql-test/r/read_only.result' --- a/mysql-test/r/read_only.result 2009-03-06 14:56:17 +0000 +++ b/mysql-test/r/read_only.result 2012-05-09 18:59:45 +0000 @@ -59,7 +59,7 @@ connection con1; select @@global.read_only; @@global.read_only -0 +1 This is prone to race conditions. Please, fix the test to remove "send" here and below. (assuming the new result is correct)

But is it correct ? Why set read_only is not blocked by a write locked myisam table?

It's not blocked as we ceased incrementing the refresh_version in this case: + /* No need to close the open tables if we just set the readonly state */ + if (!set_readonly_mode) + refresh_version++; // Force close of open tables + Right, this test with the 'send set read_only' should be either removed or updated.

Where are the tests for the changed functionality?

No specific tests yet. I was to lazy to add the new test while i was not sure i did the correct thing. Hoped to get the quick answer.

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=== modified file 'sql/sql_base.cc' --- a/sql/sql_base.cc 2012-04-19 06:16:30 +0000 +++ b/sql/sql_base.cc 2012-05-09 18:59:45 +0000 @@ -933,7 +938,8 @@ for (uint idx=0 ; idx< open_cache.records ; idx++) { TABLE *table=(TABLE*) hash_element(&open_cache,idx); - if (table->in_use) + if (table->in_use&& + (!set_readonly_mode || !table->file->has_transactions())) I wonder how this could work. The line below sets a flag *on a thread*. The task description tells "not wait for transactional tables", while your change means "not set a flag if all tables used in a thread are transactional". That is, if a thread uses both transactional and non-transactional tables, your change does nothing.

That's right, it' won't work with the mixed types of tables. But as the customer didn't ask for that, maybe the simplest solution will do here.

Back to my first question - where are the tests for this new task?

Will develop some ASAP. HF