zhaozhao.zz 131857e80a
To avoid bouncing -REDIRECT during FAILOVER (#871)
Fix #821

During the `FAILOVER` process, when conditions are met (such as when the
force time is reached or the primary and replica offsets are
consistent), the primary actively becomes the replica and transitions to
the `FAILOVER_IN_PROGRESS` state. After the primary becomes the replica,
and after handshaking and other operations, it will eventually send the
`PSYNC FAILOVER` command to the replica, after which the replica will
become the primary. This means that the upgrade of the replica to the
primary is an asynchronous operation, which implies that during the
`FAILOVER_IN_PROGRESS` state, there may be a period of time where both
nodes are replicas. In this scenario, if a `-REDIRECT` is returned, the
request will be redirected to the replica and then redirected back,
causing back and forth redirection. To avoid this situation, during the
`FAILOVER_IN_PROGRESS state`, we temporarily suspend the clients that
need to be redirected until the replica truly becomes the primary, and
then resume the execution.

---------

Signed-off-by: zhaozhao.zz <zhaozhao.zz@alibaba-inc.com>
2024-08-14 14:04:29 +08:00
..

Valkey Test Suite

Overview

Integration tests are written in Tcl, a high-level, general-purpose, interpreted, dynamic programming language [source]. runtest is the main entrance point for running integration tests. For example, to run a single test;

./runtest --single unit/your_test_name
# For additional arguments, you may refer to the `runtest` script itself.

The normal execution mode of the test suite involves starting and manipulating local valkey-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 Valkey Cluster compatibility mode.
--large-memory Enables tests that consume more than 100mb

Debugging

You can set a breakpoint and invoke a minimal debugger using the bp function.

... your test code before break-point
bp 1
... your test code after break-point

The bp 1 will give back the tcl interpreter to the developer, and allow you to interactively print local variables (through puts), run functions and so forth [source]. bp takes a single argument, which is 1 for the case above, and is used to label a breakpoint with a string. Labels are printed out when breakpoints are hit, so you can identify which breakpoint was triggered. Breakpoints can be skipped by setting the global variable ::bp_skip, and by providing the labels you want to skip.

The minimal debugger comes with the following predefined functions.

  • Press c to continue past the breakpoint.
  • Press i to print local variables.

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