In most files it was unused. We should move these to the patch which
moved out the last interesting reader from mutation_reader.hh (and added
the corresponding new header include) but its probably not worth the
effort.
Some other files still relied on mutation_reader.hh to provide reader
concurrency semaphore and some other misc reader related definitions.
The flat_mutation_reader files were conflated and contained multiple
readers, which were not strictly necessary. Splitting optimizes both
iterative compilation times, as touching rarely used readers doesn't
recompile large chunks of codebase. Total compilation times are also
improved, as the size of flat_mutation_reader.hh and
flat_mutation_reader_v2.hh have been reduced and those files are
included by many file in the codebase.
With changes
real 29m14.051s
user 168m39.071s
sys 5m13.443s
Without changes
real 30m36.203s
user 175m43.354s
sys 5m26.376s
Closes#10194
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
Move replica-oriented classes to the replica namespace. The main
classes moved are ::database, ::keyspace, and ::table, but a few
ancillary classes are also moved. There are certainly classes that
should be moved but aren't (like distributed_loader) but we have
to start somewhere.
References are adjusted treewide. In many cases, it is obvious that
a call site should not access the replica (but the data_dictionary
instead), but that is left for separate work.
scylla-gdb.py is adjusted to look for both the new and old names.
The database, keyspace, and table classes represent the replica-only
part of the objects after which they are named. Reading from a table
doesn't give you the full data, just the replica's view, and it is not
consistent since reconciliation is applied on the coordinator.
As a first step in acknowledging this, move the related files to
a replica/ subdirectory.
In commit 3e39985c7a we added the Cassandra-compatible system table
system."IndexInfo" (note the capitalized table name) which lists built
indexes. Because we already had a table of built materialized views, and
indexes are implemented as materialized views, the index list was
implemented as a virtual table based on the view list.
However, the *name* of each materialized view listed in the list of
views looks like something_index, with the suffix "_index", while the
name of the table we need to print is "something". We forgot to do this
transformation in the virtual table - and this is what this patch does.
This bug can confuse applications which use this system table to wait for
an index to be built. Several tests translated from Cassandra's unit
tests, in cassandra_tests/validation/entities/secondary_index_test.py fail
in wait_for_index() because of this incompatibility, and pass after this
patch.
This patch also changes the unit test that enshrined the previous, wrong,
behavior, to test for the correct behavior. This problem is typical of
C++ unit tests which cannot be run against Cassandra.
Fixes#8600
Unfortunately, although this patch fixes "typical" applications (including
all tests which I tried) - applications which read from IndexInfo in a
"typical" method to look for a specific index being ready, the
implementation is technically NOT correct: The problem is that index
names are not sorted in the right order, because they are sorted with
the "_index" prefix.
To give an example, the index names "a" should be listed before "a1", but
the view names "a1_index" comes before "a_index" (because in ASCII, 1
comes before underscore). I can't think of any way to fix this bug
without completely reimplementing IndexInfo in a different way - probably
based on a temporary memtable (which is fine as this is not a
performance-critical operation). We'll need to do this rewrite eventually,
and I'll open a new issue.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210509140113.1084497-1-nyh@scylladb.com>
Not used yet, this patch does all the churn of propagating a permit
to each impl.
In the next patch we will use it to track to track the memory
consumption of `_buffer`.
Now that the most prevalent users (range scan and single partition
reads) all pass valid permits we require all users to do so and
propagate the permit down towards `make_sstable_reader()`. The plan is
to use this permit for restricting the sstable readers, instead of the
semaphore the table is configured with. The various
`make_streaming_*reader()` overloads keep using the internal semaphores
as but they also create the permit before the read starts and pass it to
`make_sstable_reader()`.
The header sits in many other headers, but there's a handy
schema_fwd.hh that's tiny and contains needed declarations
for other headers. So replace shema.hh with schema_fwd.hh
in most of the headers (and remove completely from some).
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Message-Id: <20200303102050.18462-1-xemul@scylladb.com>
The former was never really more than a reader_permit with one
additional method. Currently using it doesn't even save one from any
includes. Now that readers will be using reader_permit we would have to
pass down both to mutation_source. Instead get rid of
reader_resource_tracker and just use reader_permit. Instead of making it
a last and optional parameter that is easy to ignore, make it a
first class parameter, right after schema, to signify that permits are
now a prominent part of the reader API.
This -- mostly mechanical -- patch essentially refactors mutation_source
to ask for the reader_permit instead of reader_resource_tracking and
updates all usage sites.
Many headers don't really need to include database.hh, the include can
be replaced by forward declarations and/or including the actually needed
headers directly. Some headers don't need this include at all.
Each header was verified to be compilable on its own after the change,
by including it into an empty `.cc` file and compiling it. `.cc` files
that used to get `database.hh` through headers that no longer include it
were changed to include it themselves.
The IndexInfo table tracks the secondary indexes that have already
been populated. Since our secondary index implementation is backed by
materialized views, we can virtualize that table so queries are
actually answered by built_views.
Fixes#3483
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
