With data segregation on repair, thousands of sstables are potentially
added to maintenance set which causes high latency due to stalls.
That's because N*M sstables are created by a repair,
where N = # of ranges
and M = # of segregations
For TWCS, M = # of windows.
Assuming N = 768 and M = 20, ~15k sstables end up in sstable set
To fix this problem, let's avoid performing data segregation in repair,
as offstrategy will already perform the segregation anyway.
So from now on, only N non-overlapping sstables will be added to set.
Read amplification isn't affected because a query will only touch one
sstable in maintenance set.
When offstrategy starts, it will pick all sstables from set and
compact them in a single step while performing data segregation,
so data is properly laid out before integrated into the main set.
tests:
- sstable_compaction_test.twcs_reshape_with_disjoint_set_test
- mode(dev)
- manual test using repair-based bootstrap
Fixes#9199.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20210824185043.76475-1-raphaelsc@scylladb.com>
Currently, if e.g. find_column_family throws an error,
as seen in #8776 when the table was dropped during repair,
the reader is not closed.
Use a coroutine to simplify error handling and
close the reader if an exception is caught.
Also, catch an error inside the lambda passed to make_interposer_consumer
when making the shared_sstable for streaming, and close the reader
their and return an exceptional future early, since
the reader will not be moved to sst->write_components, that assumes
ownership over it and closes it in all cases.
Fixes#8776
Test: unit(dev)
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Both streaming and repair call the distributed sstables writing with
equal lambdas each being ~30 lines of code. The only difference between
them is repair might request offstrategy compaction for new sstable.
Generalization of these two pieces save lines of codes and speeds the
release/repair/row_level.o compilation by half a minute (out of twelve).
tests: unit(dev)
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20210531133113.23003-1-xemul@scylladb.com>
