Tarantool 2.8.2

The log module now supports symbolic representation of log levels. Now it is possible to specify levels the same way as in the box.cfg{} call (gh-5882).

For example, instead of

require('log').cfg{level = 6}

it is possible to use

require('log').cfg{level = 'verbose'}

Descriptions of type mismatch error and inconsistent type error have become more informative (gh-6176).

Removed explicit cast from BOOLEAN to numeric types and vice versa (gh-4770).

For example, CAST(FALSE AS INTEGER) was 0 in version 2.8. Now it causes an error.

Removed explicit cast from VARBINARY to numeric types and vice versa (gh-4772, gh-5852).

Fixed a bug where a string that is not NULL-terminated could not be cast to BOOLEAN, even if the conversion would be successful according to the rules.

[Breaking change] fiber.wakeup() in Lua and fiber_wakeup() in C became NOP on the currently running fiber. Previously they allowed “ignoring” the next yield or sleep, which resulted in unexpected erroneous wake-ups. Calling these functions right before fiber.create() in Lua or fiber_start() in C could lead to a crash (in debug build) or undefined behaviour (in release build) (gh-6043).

There was a single use case for the previous behaviour: rescheduling in the same event loop iteration, which is not the same as fiber.sleep(0) in Lua and fiber_sleep(0) in C. It could be done in the following way:

in C:

fiber_wakeup(fiber_self());
fiber_yield();

and in Lua:

fiber.self():wakeup()
fiber.yield()

To get the same effect in C, one can now use fiber_reschedule(). In Lua, it is now impossible to reschedule the current fiber directly in the same event loop iteration. One can reschedule self through a second fiber, but it is strongly discouraged:

-- do not use this code
local self = fiber.self()
fiber.new(function() self:wakeup() end)
fiber.sleep(0)

Fixed memory leak on box.on_commit() and box.on_rollback() (gh-6025).

fiber_join() now checks if the argument is a joinable fiber. The absence of this check could lead to unpredictable results. Note that the change affects the C level only; in the Lua interface, fiber:join() protection is already enabled.

Now Tarantool yields when it scans .xlog files for the latest applied vclock and finds the right place to start recovering from. It means that the instance becomes responsive right after the box.cfg call even if an empty .xlog was not created on the previous exit.

This fix also prevents the relay from timing out when a freshly subscribed replica needs rows from the end of a relatively long (hundreds of MBs) .xlog file (gh-5979).

The counter in N rows processed log messages no longer resets on each newly recovered xlog.

Fixed a crash in JSON update on tuple/space, where the update included two or more operations that accessed fields in reversed order and these fields didn’t exist. Example: box.tuple.new({1}):update({{'=', 4, 4}, {'=', 3, 3}}) (gh-6069).

Fixed invalid results of the json module’s encode function when it was used from the Lua garbage collector. For example, this could happen in functions used as ffi.gc() (gh-6050).

Added a check for user input of the number of iproto threads: value must be greater than zero and less than or equal to 1000 (gh-6005).

Changing a listed address can no longer cause iproto threads to close the same socket several times.

Tarantool now always removes the Unix socket correctly when it exits.

Simultaneously updating a key in different transactions does not longer result in a MVCC crash (gh-6131).

Fixed a bug where memtx MVCC crashed during reading uncommitted DDL (gh-5515).

Fixed a bug where memtx MVCC crashed if an index was created in the transaction thread (gh-6137).

Fixed a MVCC segmentation fault that arose when updating the entire space concurrently (gh-5892).

Fixed a bug with failed assertion after a stress update of the same key (gh-6193).

Fixed a crash where box.snapshot could be called during an incomplete transaction (gh-6229).

Fixed console client connection failure in case of request timeout (gh-6249).

Added a missing broadcast to net.box.future:discard() so that now fibers waiting for a request result wake up when the request is discarded (gh-6250).

box.info.uuid, box.info.cluster.uuid, and tostring(decimal) with any decimal number in Lua could sometimes return garbage if there were __gc handlers in the user’s code (gh-6259).

Fixed an error message that appeared in a particular case during MVCC operation (gh-6247).

Fixed a repeatable read violation after delete (gh-6206).

Fixed a bug where the MVCC engine didn’t track the select{} hash (gh-6040).

Fixed a crash in MVCC after a drop of space with several indexes (gh-6274).

Fixed a bug where the GC could leave tuples in secondary indexes (gh-6234).

Disallow yields after DDL operations in MVCC mode. It fixes a crash that took place when several transactions referred to system spaces (gh-5998).

Fixed a bug in MVCC that happened on rollback after a DDL operation (gh-5998).

Fixed a bug where rollback resulted in unserializable behavior (gh-6325).