I'm on a fresh install of Phabricator. I cannot overcome the problem with:

Lock wait timeout exceeded; try restarting transaction

This occurs only when I try to create a new Project, or edit a user profile by clicking on "Edit" on the user's avatar.

I've tested Phabricator on both - a local database and RDS - both MariaDB, InnoDB engine - the problem occurs with both. I've also tested with the daemons running and being stopped - with the same effect.

I'm on the latest "stable" branch of Phabricator. Innodb_lock_wait_timeout is set to 50.

SHOW ENGINE INNODB STATUS reports (only part of the "Transactions" section is shown):

---TRANSACTION 0, not started
MySQL thread id 355, OS thread handle 0x7f7d846db700, query id 2304 localhost root cleaning up
---TRANSACTION 0, not started
MySQL thread id 354, OS thread handle 0x7f7d83732700, query id 2302 localhost root cleaning up
---TRANSACTION 0, not started
MySQL thread id 196, OS thread handle 0x7f7d83657700, query id 2343 localhost root init
show engine innodb status
---TRANSACTION 9093, ACTIVE 13 sec
7 lock struct(s), heap size 1184, 2 row lock(s), undo log entries 10
MySQL thread id 298, OS thread handle 0x7f7d8077b700, query id 2075 localhost root cleaning up
Trx read view will not see trx with id >= 9098, sees < 9098

SHOW FULL PROCESSLIST:

MariaDB [(none)]> show full processlist;
+-----+------+-----------+---------------------+---------+------+-------+-----------------------+----------+
| Id  | User | Host      | db                  | Command | Time | State | Info                  | Progress |
+-----+------+-----------+---------------------+---------+------+-------+-----------------------+----------+
| 196 | root | localhost | NULL                | Query   |    0 | init  | show full processlist |    0.000 |
| 292 | root | localhost | phabricator_config  | Sleep   |   48 |       | NULL                  |    0.000 |
| 293 | root | localhost | phabricator_cache   | Sleep   |   48 |       | NULL                  |    0.000 |
| 294 | root | localhost | phabricator_user    | Sleep   |   48 |       | NULL                  |    0.000 |
| 295 | root | localhost | phabricator_spaces  | Sleep   |   48 |       | NULL                  |    0.000 |
| 296 | root | localhost | phabricator_search  | Sleep   |   48 |       | NULL                  |    0.000 |
| 297 | root | localhost | phabricator_project | Sleep   |   47 |       | NULL                  |    0.000 |
| 298 | root | localhost | phabricator_project | Sleep   |   47 |       | NULL                  |    0.000 |
| 299 | root | localhost | phabricator_file    | Sleep   |   47 |       | NULL                  |    0.000 |
+-----+------+-----------+---------------------+---------+------+-------+-----------------------+----------+

The above would result either in an exception or 504 Gateway Timeout. Other post requests pass without problems - the issue relates only to adding a new project and editing a user profile - at leat I know only of these to places. Please also notice that the actual INSERT query does not seem to be executed at all. The transaction seem to hang on cleaning up.