Every evictable version will have a dummy entry at the end so that it can be
tracked in the LRU.
It is also needed to allow old versions to stay around (with
tombstones and static rows) after all rows are evicted. Such versions
must be fully discontinuous, and we need some entry to mark that.
We will need to propagate a cache_tracker reference to evict(). Instead
of evicting from destructor, do so before cache_entry gets unlinked
from the tree. Entries which are not linked, don't need to be
explicitly evicted.
This change is a preparation for introducing row-level eviction, such that entries
can be evicted from older versions without having to touch other versions.
Currently continuity flags on entries are interpreted relative to the
combined view merged from all entries. For example:
v2: <key=2, cont=1>
v1: <key=1, cont=1>
In v2, the flag on entry key=2 marks the range (1, 2) as
continuous. This is problematic because if the old version is evicted, continuity
will change in an incorrect way:
v2: <key=2, cont=1>
Here, the range (-inf, 1) would be marked as continuous, which is not true.
To solve this problem, we change the rules for continuity
interpretation in MVCC. Each version will have its own continuity,
fully specified in that version, independent of continuity of other
versions. Continuity of the snapshot will be a union of continuous
ranges in each version.
It is assumed that continuous intervals in different versions are non-
overlapping, except for points corresponding to complete rows, in
which case a later version may overlap with an older version
(overwrite). We make use of this assumption to make calculation of the
union of intervals on merging easier. I make use of the above
assumption in mutation_partition::apply_monotonically().
MVCC population of incomplete entries already almost maintains the
non-overlapping invariant, because population intervals correspond to
intervals which are incomplete in the old snapshot. The only change
needed is to ensure that both population bounds will have entries in
the latest version. Population from memtables doesn't mark any
intervals as continuous, so also conforms. The only change needed
there is to not inherit continuity flags from the old snapshot,
effectively making the new version internally discontinuous except for
row points.
The example from the beginning will become:
v2: <key=1, cont=0> <key=2, cont=1>
v1: <key=1, cont=1>
When marking a range as continuous with some rows present only in
older versions, we need to insert entries in the latest version, so
that we can mark the range as continuous. The easiest solution is to
copy the entry from the old version. Another option would be to add
support for incomplete rows and insert such instead. This way we would
avoid duplicating row contents. This optimization is deferred.
Simply copying mutations which are not fully continuous may violate
MVCC invariants, like the one about non-overlapping continuity which
will be added later. Use apply_to_incomplete() instead.
This unfortunately reduces strenght of the test, since the continuity
of the entry is now completely determined by the first version. We should
use populate() instead, but it doesn't exist yet. It could be extracted
from cache_streamed_mutation, but that's not an easy change.
This is alleviated by adding a similar test to row_cache_test_g, in a
later patch.
In commit 8af0b501a2 (gossip: wait for stabilized gossip on bootstrap)
The force_after variable was changed from int32_t to stdx::optional<int32_t>
- if (force_after > 0 && total_polls > force_after) {
+ if (force_after && total_polls > *force_after) {
Checking force_after > 0 was dropped which is wrong because force_after
is set to -1 by default. So the if branch will always be executed after
1 poll.
We always see:
[shard 0] gossip - Gossip not settled but startup forced by
skip_wait_for_gossip_to_settle. Gossp total polls: 1
even if skip_wait_for_gossip_to_settle is not set at all.
Fixes#3257
Message-Id: <845d219cea6101a7c507c13879c850a5c882e510.1520297548.git.asias@scylladb.com>
In Crypto++ v6, the `byte` typedef has been moved from the global
namespace to the CryptoPP:: namespace.
To make Scylla code compile with both old and new versions, bring the
namespace in so that the code works regardless of the scope of `byte`
definition.
Fixes#3252
Signed-off-by: Vladimir Krivopalov <vladimir@scylladb.com>
Message-Id: <60e7bfe868b778b1c9bbe15d7247db64b61bd406.1520272198.git.vladimir@scylladb.com>
"-I$full_builddir/{mode}/xxhash" doesn't resolve to a valid path, because
full_builddir is a Python variable, not a Ninja variable. In build.ninja
it appears as "-I/release/xxhash".
Since the build nevertheless works, we can remove the broken flag instead
of fixing it.
Message-Id: <20180305135919.13634-1-avi@scylladb.com>
This patch fixes an issue with test_propagation(), where the test
assumed that after the future returned from wait_for_pending(0)
resolved, the continuations set for the post operation had already
run, which is not true.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Message-Id: <20180305131908.7667-1-duarte@scylladb.com>
reader_wrapper's _timeout defaults to now(), which means to time
out immediately rather than no timeout.
Fix by switching to a time_point, defaulting to no_timeout, and
provide a compatible constructor (with a duration parameter) for
callers that do want a duration-based timeout.
Tests: mutation_reader_test (debug, release)
Message-Id: <20180305111739.31972-1-avi@scylladb.com>
* seastar f841d2d...08e02dc (3):
> future: make future::wait() a supported function
> scripts: perftune.py: don't allow cpu-mask that does't include any IRQ CPU
> Tutorial: show nice dashes in HTML
The message in question is printed with printf() which is bad by itself.
And most importantly this test uses a single .property file so this message
doesn't add any interesting information to begin with. Therefore it makes
more sense to drop it than to fix it.
Signed-off-by: Vlad Zolotarov <vladz@scylladb.com>
Message-Id: <1519661059-13325-1-git-send-email-vladz@scylladb.com>
This patch series ties up some loose ends around CQL syntax for access-control statements.
The USER-based syntax statements are all backwards compatible. ROLE-specific statements have a new syntax which is described in "cql: Make role syntax for consistent". Other statements (like GRANT) have been updated to accept role names (instead of the more restrictive `username` rule).
Fixes#3217.
Tests: unit (debug)
* 'jhk/roles_syntax/v2' of https://github.com/hakuch/scylla:
tests: Rename test for consistency
cql: Eliminate uses of legacy `username` rule
cql: Elaborate error for quoted user names
cql: Allow role names to be string literals
cql: Make role syntax more consistent
tests: Add CQL syntax tests for access-control
Since quoted names are allowed for role names, we add a more descriptive
error message when a quoted name is (erroneously) used for a user name.
This behavior is consistent with Apache Cassandra.
This patch changes the syntax for CQL statements related to roles to
favor a form like
CREATE ROLE sam WITH PASSWORD = 'shire' AND LOGIN = false;
instead of
CREATE ROLE sam WITH PASSWORD 'shire' NOLOGIN;
This new syntax has the benefit of not imposing any ordering constraints
on the modifiers for roles and being consistent with other parts of the
CQL grammar. It is also consistent with syntax in Apache Cassandra.
The old USER-based statements (CREATE USER and ALTER USER) still have
the old forms for backwards compatibility.
A previous change modified the USER-related statements to allow for the
OPTIONS option. However, this was a mistake; only the PASSWORD option
should have been allowed. This patch also corrects this mistake.
These are quick-running tests for verifying the accepted forms of CQL
statements (and fragments) related to access-control: users, roles, and
permissions.
Establishing the allowed forms of statements is helpful for reference,
but also makes syntax changes (like those expected in later patches)
clearer and more safe.
