十个bpftrace uprobe mysqld的详细案例-Go服务器开发

以下是十个使用bpftrace和uprobe跟踪mysqld的详细案例：

跟踪MySQL中执行的查询语句：

sudo bpftrace -e 'uprobe:/path/to/mysqld:query__execute_stmt_entry { printf("%s\n", user_string(args->stmt)); }'

统计MySQL中每个查询的执行时间：

sudo bpftrace -e 'uprobe:/path/to/mysqld:query__execute_stmt_entry /user_string(args->stmt) == "SELECT * FROM table_name"/ { @start[tid] = nsecs; }
                 uprobe:/path/to/mysqld:query__execute_stmt_return /@start[tid]/ { @elapsed_time = nsecs - @start[tid]; delete(@start[tid]); printf("Query took %lld nanoseconds\n", @elapsed_time); }'

检测MySQL中是否有慢查询（超过阈值）：

sudo bpftrace -e 'uprobe:/path/to/mysqld:query__execute_stmt_entry /user_string(args->stmt) != NULL/ { @start[tid] = nsecs; }
                 uprobe:/path/to/mysqld:query__execute_stmt_return /@start[tid]/ { @elapsed_time = nsecs - @start[tid]; delete(@start[tid]);
                    if (@elapsed_time > 1000000) { printf("Slow query detected! Execution time: %lld nanoseconds\n", @elapsed_time); }}'

跟踪MySQL中每个事务的开始和结束：

sudo bpftrace -e 'uprobe:/path/to/mysqld:start__transaction { printf("Transaction started\n"); }
                 uprobe:/path/to/mysqld:commit__one_phase /comm == "COMMIT"/ { printf("Transaction committed\n"); }
                 uprobe:/path/to/mysqld:rollback__storable /comm == "ROLLBACK"/ { printf("Transaction rolled back\n"); }'

统计MySQL中每个事务的执行时间：

sudo bpftrace -e 'uprobe:/path/to/mysqld:start__transaction { @start[tid] = nsecs; }
                 uprobe:/path/to/mysqld:commit__one_phase /comm == "COMMIT" && @start[tid]/ { @elapsed_time = nsecs - @start[tid]; delete(@start[tid]); printf("Transaction took %lld nanoseconds to commit\n", @elapsed_time); }'

跟踪MySQL中慢查询的执行路径：

sudo bpftrace -e 'uprobe:/path/to/mysqld:item___init_by_string_key /user_string(args->key) != NULL/ { @start[tid] = ktime; }
                 uprobe:/path/to/mysqld:MYSQLparse /@start[tid]/ { printf("%s\n", user_string(args->sql)); delete(@start[tid]); }'

统计MySQL中每个连接的请求次数：

sudo bpftrace -e 'uprobe:/path/to/mysqld:mysql_execute_command_entry { @[args->thd, args->command] = count(); } tick-1sec { clear(); }'

跟踪MySQL中的内存分配和释放操作：

sudo bpftrace -e 'uprobe:/path/to/mysqld:my_malloc /size > 0/ { @allocations[tid] = sum(args->size); }
                 uprobe:/path/to/mysqld:my_free /ptr != NULL/ { @deallocations[tid] = sum(args->ptr); }
                 tick-1sec { print(@allocations); print(@deallocations); clear(); }'

监视MySQL中锁的使用情况：

sudo bpftrace -e 'uprobe:/path/to/mysqld:mdl__acquire_lock_exclusive_entry { printf("Exclusive lock acquired\n"); }
                 uprobe:/path/to/mysqld:mdl__release_lock_exclusive_entry { printf("Exclusive lock released\n"); }
                 uprobe:/path/to/mysqld:mdl__acquire_lock_shared_entry { printf("Shared lock acquired\n"); }
                 uprobe:/path/to/mysqld:mdl__release_lock_shared_entry { printf("Shared lock released\n"); }'

跟踪MySQL中每个表的查询次数：

sudo bpftrace -e 'uprobe:/path/to/mysqld:open_table /table != NULL && user_string(args->table) != NULL/ { @[args->table] = count(); } tick-1sec { print(@); clear(); }'

请注意，这些示例假设你已经正确配置了bpftrace和mysqld的路径，并具有足够的权限来进行跟踪。在实际应用中，你可能需要根据自己的环境和需求进行相应的调整。

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