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c1e69a77a6
The problem was in a test case for Bug33507:
- when the number of active connections reaches the limit,
the server accepts only root connections. That's achieved by
accepting a connection, negotiating with the client and
checking user credentials. If it is not SUPER, the connection
is dropped.
- when the server accepts connection, it increases the counter;
- when the server drops connection, it decreases the counter;
- the race was in between of decreasing the counter and accepting
new connection:
- max_user_connections = 2;
- 2 oridinary user connections accepted;
- extra user connection is establishing;
- server checked user credentials, and sent 'Too many connections'
error;
- the client receives the error and establishes extra SUPER user
connection;
- the server however didn't decrease the counter (the extra
user connection still is "alive" in the server) -- so, the new
SUPER-user connection, will be dropped, because it exceeds
(max_user_connections + 1).
The fix is to implement "safe connect", which makes several attempts
to connect and use it in the test script.
mysql-test/r/connect.result:
Update test file.
mysql-test/t/connect.test:
Avoid races in connect.test.
mysql-test/include/connect2.inc:
Auxiliary routine to establish a connection reliably.
56 lines
977 B
PHP
56 lines
977 B
PHP
# include/connect2.inc
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#
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# SUMMARY
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#
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# Make several attempts to connect.
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#
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# USAGE
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#
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# EXAMPLE
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#
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# connect.test
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#
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--disable_query_log
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let $wait_counter= 300;
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if ($wait_timeout)
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{
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let $wait_counter= `SELECT $wait_timeout * 10`;
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}
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# Reset $wait_timeout so that its value won't be used on subsequent
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# calls, and default will be used instead.
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let $wait_timeout= 0;
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--echo # -- Establishing connection '$con_name' (user: $con_user_name)...
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while ($wait_counter)
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{
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--disable_abort_on_error
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--disable_result_log
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--connect ($con_name,localhost,$con_user_name)
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--enable_result_log
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--enable_abort_on_error
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let $error = $mysql_errno;
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if (!$error)
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{
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let $wait_counter= 0;
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}
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if ($error)
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{
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real_sleep 0.1;
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dec $wait_counter;
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}
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}
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if ($error)
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{
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--echo # -- Error: can not establish connection '$con_name'.
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}
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if (!$error)
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{
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--echo # -- Connection '$con_name' has been established.
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}
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--enable_query_log
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