title | summary | aliases | ||
---|---|---|---|---|
Maintain a TiFlash Cluster |
Learn common operations when you maintain a TiFlash cluster. |
|
This document describes how to perform common operations when you maintain a TiFlash cluster, including checking the TiFlash version. This document also introduces critical logs and a system table of TiFlash.
There are two ways to check the TiFlash version:
-
If the binary file name of TiFlash is
tiflash
, you can check the version by executing the./tiflash version
command.However, to execute the above command, you need to add the directory path which includes the
libtiflash_proxy.so
dynamic library to theLD_LIBRARY_PATH
environment variable. This is because the running of TiFlash relies on thelibtiflash_proxy.so
dynamic library.For example, when
tiflash
andlibtiflash_proxy.so
are in the same directory, you can first switch to this directory, and then use the following command to check the TiFlash version:{{< copyable "shell-regular" >}}
LD_LIBRARY_PATH=./ ./tiflash version
-
Check the TiFlash version by referring to the TiFlash log. For the log path, see the
[logger]
part in thetiflash.toml
file. For example:<information>: TiFlash version: TiFlash 0.2.0 master-375035282451103999f3863c691e2fc2
Log Information | Log Description |
---|---|
[ 23 ] <Information> KVStore: Start to persist [region 47, applied: term 6 index 10] |
Data starts to be replicated (the number in the square brackets at the start of the log refers to the thread ID |
[ 30 ] <Debug> CoprocessorHandler: grpc::Status DB::CoprocessorHandler::execute() |
Handling DAG request, that is, TiFlash starts to handle a Coprocessor request |
[ 30 ] <Debug> CoprocessorHandler: grpc::Status DB::CoprocessorHandler::execute() |
Handling DAG request done, that is, TiFlash finishes handling a Coprocessor request |
You can find the beginning or the end of a Coprocessor request, and then locate the related logs of the Coprocessor request through the thread ID printed at the start of the log.
The column names and their descriptions of the information_schema.tiflash_replica
system table are as follows:
Column Name | Description |
---|---|
TABLE_SCHEMA | database name |
TABLE_NAME | table name |
TABLE_ID | table ID |
REPLICA_COUNT | number of TiFlash replicas |
AVAILABLE | available or not (0/1) |
PROGRESS | replication progress [0.0~1.0] |