Problem is that in recent kernels io_uring may return completions BEFORE
clearing the submission queue. I.e. for example its capacity is 512, there
were 512 requests, one of them completed, so when the request completion is
processed the queue "should have" 1 free slot. But sometimes it doesn't because
io_uring doesn't always clear the submission queue before sending CQE :-/
Fixes client hangs possible after stopping & restarting an osd.
Hangs happened when a connection was closed in the middle of reading a READ
operation reply from the network. In this case the operation being read was
in read_op and the client didn't free it when closing the connection.
Test case for msgr_read.cpp:
- Partially read reply for a READ operation
- stop_client()
- Check that the READ operation returns EPIPE
The bug was actually introduced in 0.5.11.
etcd connection stability, clang & elbrus support
- Fix build under CLang and Elbrus LCC compilers, making Vitastor compatible
with Elbrus CPUs :)
- Completely fix the bug where OSDs didn't connect to peers and incorrectly marked
PGs as incomplete
- Limit I/O depth for deletes the same way as for small writes. Makes OSD crashes
with "Assertion failed: sqe != NULL" during image deletion go away
- Fix a very old, but rare, journaling bug (credits to https://github.com/mirrorll)
- Fix flushing of unclean journaled objects leading to OSDs sometimes hanging
after failover in EC setups (bug was introduced in 0.6.7)
- Fix several problems that could prevent smooth operation of a Vitastor cluster
under the condition of partial etcd failure:
- OSDs could randomly fail due to too strict error handling
- New clients and OSDs could be unable to start because of the lack of retries
- CLI could fail some commands because of the lack of retries
- Monitor could stop receiving state updates because of the lack of websocket pings
- Fix monitor being unable to rebalance PGs after a downscale of pool pg_size (3->2)
- Exit with failure when trying to nbd map or benchmark a non-existing image
- Use HTTP keep-alive for etcd connections
- Allow to configure etcd request timeouts and retries
- Allow to configure NBD timeout, max devices and partitions, and set default to
up to 64 devices with up to 3 partitions each
Build problems fixed:
- void* pointer arithmetic which is a GNU extension (works as byte*)
- "variable size object may not be initialized" which is OK under GCC
- nullptr_t related error in json11 (it lacks 'operator <' in clang)
Warnings fixed:
- empty nested struct initializer { 0 } replaced by {}
- removed several unused lambda captures
Vitaliy Filippov
