This will be used together with sstables::read_range_rows
to migrate sstables::as_mutation_source().
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Don't use streamed_mutation in mp_row_consumer
and sstable_mutation_reader.
Also use sstable_mutation_reader in sstable::read_row.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
It will be used in sstable_mutation_reader when the reader
will be used to implement sstable::read_row.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Streamed mutation won't be used any more so get_next_partition
and on_partition_finished are more suitable names.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Those methods have to be below sstable_mutation_reader because
they will be using the reader instead of streamed_mutation.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
This is the first step which still uses streamed_mutation.
Next step will be to get rid of streamed_mutation.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
The wrapper is no longer needed because
read_range_rows returns ::mutation_reader instead of
sstables::mutation_reader and the reader returned from
it keeps the pointer to shared_sstable that was used to
create the reader.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
This will make migration to flat_mutation_reader much
easier and sstables::mutation_reader is going away with
this migration anyway.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Before this patch mp_row_consumer was using sstable_streamed_mutation
in two ways:
1. Populate sstable_streamed_mutation's buffer with mutation_fragments
2. Advance sstable_streamed_mutation's sstable_data_source to new position.
We can easily reduce those dependencies only to the first one.
This will reduce the coupling between those classes and simplify
the flow of execution.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
query::full_slice doesn't select any regular or static columns, which
is at odds with the expectations of its users. This patch replaces it
with the schema::full_slice() version.
Refs #2885
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Message-Id: <1507732800-9448-2-git-send-email-duarte@scylladb.com>
For every finished compaction, we were calculating shards for all
existing tables. With ignore_msb set to 0, it's probably not a big
deal, but if ignore_msb is like 12 and LCS is used (meaning thousands
of tables possibly), the operation may stall the reactor for a
considerable amount of time. That's fixed by caching shards.
Fixes#2875.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20171011053424.22308-1-raphaelsc@scylladb.com>
"Currently restricting_mutation_reader restricts mutation_readears on a
count basis. This is inaccurate on multiple levels. The reader might be
a combined_mutation_reader, which might be composed of multiple
individual readers, whose number might change during the lifetime of the
reader. The memory consumption of the readers can vary and may change
during the lifetime of the reader as well.
To remedy this, make the restriction memory-consumption based. The
restricting semaphore is now configured with the amound of memory
(bytes) that its readers are allowed to consume in total. New readers
consume 128k units up-front to account for read-ahead buffers, and then
consume additional units for any buffer (returned
from input_stream<>::read()) they keep around.
Like before, readers already allowed to read will not be blocked,
instead new readers will be blocked on their first read if all the units
all consumed.
Fixes #2692."
* 'bdenes/restricting_mutation_reader-v5' of https://github.com/denesb/scylla:
Update reader restriction related metrics
Add restricted_reader_test unit test
restricted_mutation_reader: restrict based-on memory consumption
mutation_reader.hh: Move restricted_reader related code
"
The original motivation for the "utils: introduce a loading_shared_values" series was a hinted handoff work where
I needed an on-demand asynchronously loading key-value container (a replica address to a commitlog instance map).
It turned out that we already have the classes that do almost what I needed:
- utils::loading_cache
- sstables::shared_index_lists
Therefore it made sense to find a common ground, unify this functionality and reuse the code both in the classes above and in the
new hinted handoff code.
This series introduces the utils::loading_shared_values that generalizes the sstables::shared_index_lists
API on top of bi::unordered_set with the rehashing logic from the utils::loading_cache triggered by an addition
of an entry to the set (PATCH1).
Then it reworks the sstables::shared_index_lists and utils::loading_cache on top of the new class (PATCH2 and PATCH3).
PATCH4 optimizes the loading_cache for the long timer period use case.
But then we have discovered that we have another "customer" for the loading_cache. Apparently our prepared statements cache
had a birth flaw - it was unlimited in size - unless the corresponding keyspace and/or table are modified/dropped the entries
are never evicted. We clearly need to limit its size and it would also make sense to evict the cache entries that haven't been
used long enough.
This seems like a perfect match for a utils::loading_cache except for prepared statements don't need to be reloaded after
they are created.
Patches starting from PATCH5 are dealing with adding the utils::loading_cache the missing functionality (like making the "reloading"
conditional and adding the synchronous methods like find(key)) and then transitioning the CQL and Thrift prepared statements
caches to utils::loading_cache.
This also fixes #2474."
* 'evict_unused_prepared-v5' of https://github.com/vladzcloudius/scylla:
tests: loading_cache_test: initial commit
cql3::query_processor: implement CQL and Thrift prepared statements caches using cql3::prepared_statements_cache
cql3: prepared statements cache on top of loading_cache
utils::loading_cache: make the size limitation more strict
utils::loading_cache: added static_asserts for checking the callbacks signatures
utils::loading_cache: add a bunch of standard synchronous methods
utils::loading_cache: add the ability to create a cache that would not reload the values
utils::loading_cache: add the ability to work with not-copy-constructable values
utils::loading_cache: add EntrySize template parameter
utils::loading_cache: rework on top of utils::loading_shared_values
sstables::shared_index_list: use utils::loading_shared_values
utils: introduce loading_shared_values
Restrict readers based on their memory consumption, instead of the count
of the top-level readers. To do this an interposer is installed at the
input_stream level which tracks buffers emmited by the stream. This way
we can have an accurate picture of the readers' actual memory
consumption.
New readers will consume 16k units from the semaphore up-front. This is
to account their own memory-consumption, apart from the buffers they
will allocate. Creating the reader will be deferred to when there are
enough resources to create it. As before only new readers will be
blocked on an exhausted semaphore, existing readers can continue to
work.
"Currently restricting_mutation_reader restricts mutation_readears on a
count basis. This is inaccurate on multiple levels. The reader might be
a combined_mutation_reader, which might be composed of multiple
individual readers, whose number might change during the lifetime of the
reader. The memory consumption of the readers can vary and may change
during the lifetime of the reader as well.
To remedy this, make the restriction memory-consumption based. The
restricting semaphore is now configured with the amound of memory
(bytes) that its readers are allowed to consume in total. New readers
consume 128k units up-front to account for read-ahead buffers, and then
consume additional units for any buffer (returned
from input_stream<>::read()) they keep around.
Like before, readers already allowed to read will not be blocked,
instead new readers will be blocked on their first read if all the units
all consumed."
Fixes#2692.
* 'bdenes/restricting_mutation_reader-v4' of https://github.com/denesb/scylla:
Update reader restriction related metrics
Add restricted_reader_test unit test
restricted_mutation_reader: restrict based-on memory consumption
mutation_reader.hh: Move restricted_reader related code
The reason to do that is because compaction can deadlock if refresh
disables write which waits for compaction, and compaction in turn
waits for dirty memory[1] that would be released by memtable write.
Dirty memory manager for non-system cfs was being used for system cfs,
which was useful for exposing this problem.
[1]: when updating compaction history.
Fixes#2769.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20170918215238.9810-2-raphaelsc@scylladb.com>
Restrict readers based on their memory consumption, instead of the count
of the top-level readers. To do this an interposer is installed at the
input_stream level which tracks buffers emmited by the stream. This way
we can have an accurate picture of the readers' actual memory
consumption.
New readers will consume 16k units from the semaphore up-front. This is
to account their own memory-consumption, apart from the buffers they
will allocate. Creating the reader will be deferred to when there are
enough resources to create it. As before only new readers will be
blocked on an exhausted semaphore, existing readers can continue to
work.
When incremental_reader_selector is used for compaction, it will
first call incremental selector of partitioned sstable set with
minimum token that will result in first interval being skipped,
which means not everything being compacted. The interval is
skipped because iterator is incorrectly advanced when token
lies before it.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20170918021446.15920-1-raphaelsc@scylladb.com>
Since utils::loading_shared_values API is based on the original shared_index_list
this change is mostly a drop-in replacement of the corresponding parts.
Signed-off-by: Vlad Zolotarov <vladz@scylladb.com>
Soon I am about to introduce a read monitor, and pairing infrastructure
to manage it. Having it all living in sstables.hh force to include it
everytime, even in places that don't really need it.
Move to its own header.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
filter.cc has just two smallish functions, which are part of the sstable
class. Move them to sstables.cc where the rest of the class members are defined.
Message-Id: <20170912080541.7836-1-avi@scylladb.com>
Use the lw_shared_ptr deleter support to define shared_sstable without
pulling the definition of class sstable, reducing compile time and
dependencies if only shared_sstable is needed.
