内存优化:增大shared_buffers、work_mem。 IO优化:使用 SSD 存储,调整effective_io_concurrency。 并行查询:设置max_parallel_workers和max_parallel_workers_per_gather。 3. 维护策略 自动清理:配置pg_cron定期清理过期分区。 统计信息更新:定时运行ANALYZE或autovacuum调优。 监控:使用pg_stat_activity、pg_stat_statem...
bgwriter_lru_maxpages = 500 effective_io_concurrency = 0 max_parallel_workers_per_gather = 0 wal_level = minimal fsync = on synchronous_commit = on full_page_writes = on wal_buffers = 32MB checkpoint_timeout = 15min max_wal_size = 64GB min_wal_size = 16GB checkpoint_completion_target ...
PG发展路线是相对保守的,即使在这样的趋势下,已经在多个方面使用了并行技术。 利用部分OS系统调度的并行IO调度(effective_io_concurrency,已完成); 并行逻辑备份和恢复技术(已完成); 并行执行器(in pg96)。 对于并行执行器,也就是本文讨论的内容,相对于其他的技术点难度显然大得多。 对于目前的架构,单个SQL任务的...
因此,设置为 1.0 表示一种“刚刚好的”策略,这种策略会写出正好符合预测值的数目的缓冲区,更大大的值可以为需求高峰提供某种缓冲,默认值是 2.0。 effective_io_concurrency:设置了该值,磁盘的预读会失效,顺序扫描和索引扫描都可以利用磁盘预读,建议关闭,默认值为 1。 max_worker_processes:系统能够支持的后台进程的...
创建一个用于流复制的用户账户repuser,密码123456 sudo -u postgres psql create user repuser replication login password'123456'; \q退出 关于pg的操作最好全部在postgres这个帐号下 mkdir -p pg_ha_config vim pg_hba.conf local all postgres peer ...
单次IO请求响应较高,在0.06毫秒; 系统调用占用的CPU百分比较高; 数据库获取快照占用CPU较高,需要PostgreSQL代码层优化,本文暂时不涉及。 阶段3 TPC-C 优化 开启PostgreSQL 预读, 预读数(n-1), 仅仅对hash 聚合有效, 有兴趣的同学可以看看PostgreSQL代码。n是条带数, 所以本例case effective_io_concurrency = 2...
为一个特定表空间设定其中一个值将覆盖规划器对该表空间中表页读取的 常规代价估计,常规代价估计是由同名的配置参数所建立(见 seq_page_cost、 random_page_cost、effective_io_concurrency)。如果一个表空间位于一个 比其他 I/O 子系统更慢或者更快的磁盘上,这些参数就能发挥作用。
.' tcp_keepalives_idle = 60 tcp_keepalives_interval = 10 tcp_keepalives_count = 0 shared_buffers = 32GB huge_pages = on maintenance_work_mem = 1GB dynamic_shared_memory_type = posix vacuum_cost_delay = 0 bgwriter_delay = 10ms bgwriter_lru_maxpages = 500 effective_io_concurrency = ...
degree controlled by effective_io_concurrency, I'll probably look for something else. Suggestions for interesting index types to look at streamifying are very welcome! Hmm. If that's really true about HNSW though, then there may still be ...
off fsync = off synchronous_commit = off full_page_writes = off shared_buffers = 512MB work_mem = 64MB maintenance_work_mem = 1024MB wal_buffers = 16MB checkpoint_segments = 64 checkpoint_completion_target = 0.9 random_page_cost = 2.0 cpu_tuple_cost = 0.05 effective_io_concurrency = 2...