Mingyi Kang f8ac5a6503
Hyperloglog avoid allocate more than 'server.hll_sparse_max_bytes' bytes of memory for sparse representation (#11438)
Before this PR, we use sdsMakeRoomFor() to expand the size of hyperloglog
string (sparse representation). And because sdsMakeRoomFor() uses a greedy
strategy (allocate about twice what we need), the memory we allocated for the
hyperloglog may be more than `server.hll_sparse_max_bytes` bytes.
The memory more than` server.hll_sparse_max_bytes` will be wasted.

In this pull request, tone down the greediness of the allocation growth, and also
make sure it'll never request more than `server.hll_sparse_max_bytes`.

This could in theory mean the size of the hyperloglog string is insufficient for the
increment we need, should be ok since in this case we promote the hyperloglog
to dense representation, an assertion was added to make sure.

This PR also add some tests and fixes some typo and indentation issues.
2022-11-28 17:35:31 +02:00
..

Redis Test Suite

The normal execution mode of the test suite involves starting and manipulating local redis-server instances, inspecting process state, log files, etc.

The test suite also supports execution against an external server, which is enabled using the --host and --port parameters. When executing against an external server, tests tagged external:skip are skipped.

There are additional runtime options that can further adjust the test suite to match different external server configurations:

Option Impact
--singledb Only use database 0, don't assume others are supported.
--ignore-encoding Skip all checks for specific encoding.
--ignore-digest Skip key value digest validations.
--cluster-mode Run in strict Redis Cluster compatibility mode.
--large-memory Enables tests that consume more than 100mb

Tags

Tags are applied to tests to classify them according to the subsystem they test, but also to indicate compatibility with different run modes and required capabilities.

Tags can be applied in different context levels:

  • start_server context
  • tags context that bundles several tests together
  • A single test context.

The following compatibility and capability tags are currently used:

Tag Indicates
external:skip Not compatible with external servers.
cluster:skip Not compatible with --cluster-mode.
large-memory Test that requires more than 100mb
tls:skip Not compatible with --tls.
needs:repl Uses replication and needs to be able to SYNC from server.
needs:debug Uses the DEBUG command or other debugging focused commands (like OBJECT REFCOUNT).
needs:pfdebug Uses the PFDEBUG command.
needs:config-maxmemory Uses CONFIG SET to manipulate memory limit, eviction policies, etc.
needs:config-resetstat Uses CONFIG RESETSTAT to reset statistics.
needs:reset Uses RESET to reset client connections.
needs:save Uses SAVE or BGSAVE to create an RDB file.

When using an external server (--host and --port), filtering using the external:skip tags is done automatically.

When using --cluster-mode, filtering using the cluster:skip tag is done automatically.

When not using --large-memory, filtering using the largemem:skip tag is done automatically.

In addition, it is possible to specify additional configuration. For example, to run tests on a server that does not permit SYNC use:

./runtest --host <host> --port <port> --tags -needs:repl