Different request types have different timeouts (for example,
read requests have shorter timeouts than truncate requests), and
also different request sources have different timeouts (for example,
an internal local query wants infinite timeout while a user query
has a user-defined timeout).
To allow for this, define two types: timeout_config represents the
timeout configuration for a source (e.g. user), while
timeout_config_selector represents the request type, and is used
to select a timeout within a timeout configuration. The latter is
implemented as a pointer-to-member.
Also introduce an infinite timeout configuration for internal
queries.
We keep track of all updates and store the minimal values of timestamps,
TTLs and local deletion times across all the inserted data.
These values are written as a part of serialization_header for
Statistics.db and used for delta-encoding values when writing Data.db
file in SSTables 3.0 (mc) format.
For #1969.
Signed-off-by: Vladimir Krivopalov <vladimir@scylladb.com>
Instead of lazily-initializing the regular base column in the view's
PK field, explicitly initialize it. This will be used by future
patches that don't have access to the schema when wanting to obtain
that column.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
The patch fixes a bug introduce by commit 089b54f2d2.
This bug exhibited when master was deployed in an attempt to populate
materialised views. The nodes restarted in the middle and they were not able
to come back.
The fix is to remember formats and versions of sstables for every generation.
Fixes: #3324.
Signed-off-by: Daniel Fiala <daniel@scylladb.com>
Message-Id: <20180410083114.17315-1-daniel@scylladb.com>
After f59f423f3c, sstable is loaded only at shards
that own it so as to reduce the sstable load overhead.
The problem is that a sstable may no longer be forwarded to a shard that needs to
be aware of its existence which would result in that sstable generation being
reallocated for a write request.
That would result in a failure as follow:
"SSTable write failed due to existence of TOC file for generation..."
This can be fixed by forwarding any sstable at load to all its owner shards
*and* the shard responsible for its generation, which is determined as follow:
s = generation % smp::count
Fixes#3273.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20180405035245.30194-1-raphaelsc@scylladb.com>
The populate_views() function takes a set of views to update, a
tokento select base table partitions, and the set of sstables to
query. This lays the foundation for a view building mechanism to exist,
which walks over a given base table, reads data token-by-token,
calculates view updates (in a simplified way, compared to the existing
functions that push view updates), and sends them to the paired view
replicas.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
This patch adds a mechanism to class column_family through which we
can synchronize with in-progress writes. This is useful for code that,
after some modification, needs to ensure that new writes will see it
before it can proceed.
In particular, this will be used by the view building code, which needs
to wait until the in-progress writes, which may have missed that there
is now a view, is observable to the view building code.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
While we now send view mutations asynchronously in the normal view
write path, other processes interested in sending view updates, such
as streaming or view building, may wish to do it synchronously.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Since we just keep retrying, this can cause Scylla to not shutdown for
a while.
The data will be safe in the commit log.
Note that this patch doesn't fix the issue when shutdown goes through
storage_service::drain_on_shutdown - more work is required to handle
that case.
Ref #3318.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Message-Id: <20180324140822.3743-3-duarte@scylladb.com>
In column_family::try_flush_memtable_to_sstable, the handle_exception()
block is on the inside of the continuations to
write_memtable_to_sstable(), which, if it fails, will leave the
sstable in the compaction_backlog_tracker::_ongoing_writes map, which
will waste disk space, and that sstable will map to a dangling pointer
to a destroyed database_sstable_write_monitor, which causes a seg
fault when accessed (for example, through the backlog_controller,
which accounts the _ongoing_writes when calculating the backlog).
Fix this by increasing the scope of handle_exception().
Fixes#3315
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Message-Id: <20180324140822.3743-2-duarte@scylladb.com>
When we introduced the CPU scheduler, we have also introduced a group
for commitlog - but never used it. There is also doubtful value in
separating reads from writes, since they are often part of the same
workload.
To accomodate for that, let's rename the query group to "statement"
(query is not incorrect, just confusing), and move the write path,
currently ungrouped, inside it.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
We are flushing the streaming memtables with streaming priority, but
applying the mutations themselves is still done with normal priorities.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
"
These patches add support for C* 2.2 file(name) format.
Namely:
* It forces Scylla to write files in la format.
* Adds storage-service feature for them.
* cf and ks are determined from directory, not from file-name (for 2.2 format).
* Adds some other fixes to make dtest happy.
* Unit tests work with la format or with both formats.
"
* 'danfiala/filename-format-2.2-v4' of https://github.com/hagrid-the-developer/scylla:
tests/sstables: Tests use la format or iterate over both formats.
tests/sstables: Helper functions support 2.2 format directory structure.
stables: Use 2.2 (la) format as a default format to store sstables if it is enabled by feature-bits.
storage_service: Support la sstable storage format as a feature.
sstables: make_descriptor accepts sstable-directory, because it is necessary to determine cf and ks in 2.2 format.
sstables: Throw more detail exception for unknown item in reverse_map.
sstables/compaction: Suppress NaN in a report of a throughput.
Add the following counters:
(1) querier_cache_lookups
(2) querier_cache_misses
(3) querier_cache_drops
(4) querier_cache_time_based_evictions
(5) querier_cache_resource_based_evictions
(6) querier_cache_memory_based_evictions
(6) querier_cache_population
(1) counts the total number of querier cache lookups. Not all
page-fetches will result in a querier lookup. For example the first page
of a query will not do a lookup as there was no previous page to reuse
the querier from. The second, and all subsequent pages however should
attempt to reuse the querier from the previous page.
(2) counts the subset of (1) where the read have missed the querier
cache (failed to find a matching saved querier).
(3) counts the subset of (1) where the querier was recalled and dropped
immediately. This can happen for example if the querier was at the wrong
position.
(4) counts the cached queriers that were evicted due to their TTL
expiring.
(5) counts the cached queriers that were evicted due to reader-resource
(those limited by reader-concurrency limits) shortage.
(6) counts the cached queriers that were evicted due to reaching the
cache's memory limits (currently set to 4% of the shards' memory).
(7) is the current number of entries in the cache
Note:
* The count of cache hits can be derived from these counters as
(1) - (2).
* cache_drop (3) also implies a cache hit (see above). This means that
the number of actually reused queriers is:
(1) - (2) - (3)
Readers serving user-reads need to obtain a permit to start reading.
There exists a restriction on how much active readers can be admitted
based on their count and their memory onsumption.
Since the saved readers of cached queriers are techically active (they
hold a permit) they can block new readers from obtaining a permit.
New readers have a higher priority because a cached reader might be
abandoned or used later at best so in the face of memory pressure we
evict cached readers to free up permits for new readers.
Cached queriers are evicted in LRU order as the oldest queriers are the
most likely to be evicted based on their TTL anyway.
Use the querier_cache (represented by the passed-in
querier_cache_context) object to lookup saved queriers at the start of
the page and save them at the end of it if it is likely that there will
be more page requests.
"
Adds extension points to schema/sstables to enable hooking in
stuff, like, say, something that modifies how sstable disk io
works. (Cough, cough, *encryption*)
Extensions are processed as property keywords in CQL. To add
an extension, a "module" must register it into the extensions
object on boot time. To avoid globals (and yet don't),
extensions are reachable from config (and thus from db).
Table/view tables already contain an extension element, so
we utilize this to persist config.
schema_tables tables/views from mutations now require a "context"
object (currently only extensions, but abstracted for easier
further changes.
Because of how schemas currently operate, there is a super
lame workaround to allow "schema_registry" access to config
and by extension extensions. DB, upon instansiation, calls
a thread local global "init" in schema_registry and registers
the config. It, in turn, can then call table_from_mutations
as required.
Includes the (modified) patch to encapsulate compression
into objects, mainly because it is nice to encapsulate, and
isolate a little.
"
* 'calle/extensions-v5' of github.com:scylladb/seastar-dev:
extensions: Small unit test
sstables: Process extensions on file open
sstables::types: Add optional extensions attribute to scylla metadata
sstables::disk_types: Add hash and comparator(sstring) to disk_string
schema_tables: Load/save extensions table
cql: Add schema extensions processing to properties
schema_tables: Require context object in schema load path
schema_tables: Add opaque context object
config_file_impl: Remove ostream operators
main/init: Formalize configurables + add extensions to init call
db::config: Add extensions as a config sub-object
db::extensions: Configuration object to store various extensions
cql3::statements::property_definitions: Use std::variant instead of any
sstables: Add extension type for wrapping file io
schema: Add opaque type to represent extensions
sstables::compress/compress: Make compression a virtual object
Make sure idx will not be equal to _control_points.size() (and thus
overflow the vector) when looking for the first control-point with
a backlog not smaller then the current one, by stopping when it's equal
to _control_points.size() - 1.
Signed-off-by: Botond Dénes <bdenes@scylladb.com>
Message-Id: <47841592792573d820650d570fa1ab7e58bdac2c.1518700405.git.bdenes@scylladb.com>
Before 312bd9ce25, boot had to call all shards for each sstable
such that they would agree/disagree on their deletion, an atomic
deletion manager requirement.
After its removal, we can afford to call only the shards that own
a given sstable.
Reducing the operation on each sstable from (SSTABLES) * (SHARD_COUNT)
to usually (SSTABLES). It may be the same as before after resharding,
but resharding is an one-off operation.
Boot time should be significantly reduced for nodes with a high smp
count and column family using leveled strategy (which can end up with
thousands of sstables).
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <20180220032554.17776-1-raphaelsc@scylladb.com>
"The motivation is that it's no longer needed after new resharding
algorithm that is the sole responsible for working with shared
sstables and regular compaction will not work with those!
So resharding will schedule deletion of shared sstables once it's
certain that shards that own them have the new unshared sstables.
The manager was needed for orchestrating deletion of shared sstable
across shards. It brings extra complexity that's not longer needed,
and it was also overloading shard 0, but the latter could have
been fixed.
Tests:
- unit: release mode
- dtest: resharding_test.py"
* 'remove_atomic_deletion_manager_v2' of github.com:raphaelsc/scylla:
Remove SSTable's atomic deletion manager
Stop using SSTable's atomic deletion manager
database: split column_family::rebuild_sstable_list
The motivation is that it's no longer needed after new resharding
algorithm that is the sole responsible for working with shared
sstables and regular compaction will not work with those!
So resharding will schedule deletion of shared sstables once it's
certain that shards that own them have the new unshared sstables.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
The motivation is that resharding will not want the code that is
specific to regular compaction after atomic deletion is removed.
Resharding will eventually only need to replace old tables with
new ones, and it will be in charge of deletion of old tables.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
We have had so far an I/O controller, for compactions and memtables, and
a CPU controller, for memtables only -- since the scheduling was still
quota-based.
Now that the CPU scheduler is fully functional, it is time to do away
with the differences and integrate them both into one. We now have a
memtable controller and a compaction controller, and they control both
CPU and I/O.
In the future, we may want to control processes that don't do one of
them, like cache updates. If that ever happens, we'll try to make
controlling one of them optional. But for now, since the I/O and CPU
controllers for our main two processes would look exactly the same we
should integrate them.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
We have merged the I/O controller without this, but we want to integrate
the CPU and I/O controllers into one. Currently, the quota can be
statically set for the CPU controller. For now, until we gain more
experience with it we should allow a static value to override the
controller's output as well.
That is particularly important since we don't yet control some
strategies like LCS and the time-based ones. Users in the field may be
using one of those strategies with a static value for background quota.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
It no longer makes sense now that we have the full scheduler +
controllers. In its lieu, we will provide an option to statically set
the controller's shares as a safe guard against us getting this wrong.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
Because execution stages defer and batch processing of the function
they run, they escape their fiber's context and therefore the
scheduling group.
Fix (for data_query) by initializing the execution_stage with the
query scheduling_group. To do that we have to move the execution
stage into the database object, so it has access to the scheduling
group during initialization.
Set up scheduling groups for streaming, compaction, memtable flush, query,
and commitlog.
The background writer scheduling group is retired; it is split into
the memtable flush and compaction groups.
Comments from Glauber:
This patch is based in a patch from Avi with the same subject, but the
differences are signficant enough so that I reset authorship. In
particular:
1) A bug/regression is fixed with the boundary calculations for the
memtable controller sampling function.
2) A leftover is removed, where after flushing a memtable we would
go back to the main group before going to the cache group again
3) As per Tomek's suggestion, now the submission of compactions
themselves are run in the compaction scheduling group. Having that
working is what changes this patch the most: we now store the
scheduling group in the compaction manager and let the compaction
manager itself enforce the scheduling group.
Signed-off-by: Glauber Costa <glauber@scylladb.com>
thread_scheduling_groups are converted to plain scheduling_group. Due to
differences in initialization (scheduling_group initializtion defers), we
create the scheduling_groups in main.cc and propagate them to users via
a new class database_config.
The sstable writer loses its thread_scheduling_group parameter and instead
inherits scheduling from its caller.
Since shares are in the 1-1000 range vs. 0-1 for thread scheduling quotas,
the flush controller was adjusted to return values within the higher ranges.
Requires "workaround" fix for schema_registry and frozen_mutation, since
the former is a free-float thread local, and the latter is a pure data
carrier. frozen_schema can take a parameter for unfreeze, but schema
registry requires being told which the system extensions are.
Introduce class result_options to carry result options through the
request pipeline, which at this point mean the result type and the
digest algorithm. This class allows us to encapsulate the concrete
digest algorithm to use.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Before this patch, our Materialized Views implementation can produce
incorrect results when given concurrent updates of the same base-table
row. Such concurrent updates may result, in certain cases, in two
different rows added to the view table, instead of just one with the latest
data. In this patch we we add locking which serializes the two conflicting
updates, and solves this problem. The locking for a single base-table
column_family is implemented by the row_locker class introduced in a
previous patch.
A long comment in the code of this patch explains in more detail why
this locking is needed, when, and what types of locks are needed: We
sometimes need to lock a single clustering row, sometimes an entire
partition, sometimes an exclusive lock and sometimes a shared lock.
Fixes#3168
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
