## Issue: When a dict has a long chain or the length of the chain is longer than the number of samples, we will never be able to sample the elements at the end of the chain using dictGetSomeKeys(). This could mean that SRANDMEMBER can be hang in and endless loop. The most severe case, is the pathological case of when someone uses SCAN+DEL or SSCAN+SREM creating an unevenly distributed dict. This was amplified by the recent change in #11692 which prevented a down-sizing rehashing while there is a fork. ## Solution 1. Before, we will stop sampling when we reach the maximum number of samples, even if there is more data after the current chain. Now when we reach the maximum we use the Reservoir Sampling algorithm to fairly sample the end of the chain that cannot be sampled 2. Fix the rehashing code, so that the same as it allows rehashing for up-sizing during fork when the ratio is extreme, it will allow it for down-sizing as well. Issue was introduced (or became more severe) by #11692 Co-authored-by: Oran Agra <oran@redislabs.com> |
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| assets | ||
| cluster | ||
| helpers | ||
| integration | ||
| modules | ||
| sentinel | ||
| support | ||
| tmp | ||
| unit | ||
| README.md | ||
| instances.tcl | ||
| test_helper.tcl | ||
README.md
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_servercontexttagscontext 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