matt traceroute(mtr) script

Somebody made a wild experiment in the MySQL server code and introduced a

horrible bug. The bug is that sometimes INSERT returns an error

"Cannot execute statement in a READ ONLY transaction." instead of succeeding.

The bug is elusive and only happens rarely when lots of INSERTs and SELECTs

are stormed into the MySQL server in parallel. A classic race condition.

The bug is in the "5.6" branch in this Git repository:

"git@[login to view URL]:vasild/[login to view URL]". You have spent a few long days running

zillion INSERTs and SELECTs trying to catch this and have finally nailed it down

to 06785398b2f. You are sure that this commit introduces the bug.

task is to write a deterministic mtr test that demonstrates the bug. The

test should deterministically fail if the bug is present and pass if the bug is

absent. Write your test under "mysql-test/t/[login to view URL]" and execute it like

"MYSQL_BUILD_DIRECTORY/mysql-test$ ./mtr [login to view URL]". Record the expected result

in "mysql-test/r/[login to view URL]" with "./mtr --record [login to view URL]". You may have to

modify the MySQL source code and add some synchronization points to it. Prepare

a patch that contains the new test, its corresponding .result file and any

changes to MySQL and send it to vidhvidhi@[login to view URL]

Useful resources:

* [login to view URL]

* [login to view URL]

* The mountain of existent mtr tests (*.test) under mysql-test/ in the MySQL

source. Hint: grep for DEBUG_SYNC, WAIT_FOR and SIGNAL in mysql-test/.

if you have more questions regarding it, email me!

Git MySQL

Projektazonosító: #16030859

A projektről