index_size - Checks the size of indexes only. last_analyze - Check the maximum time in seconds since any one table has been analyzed. last_autoanalyze - Check the maximum time in seconds since any one table has been autoanalyzed. last_autovacuum - Check the maximum time in seconds since ...
mydb=# create table testfragement(tid int,tname varchar(20));CREATE TABLE mydb=# insert into testfragement select n,'myname_'||n from generate_series(1,50000) n;INSERT 0 50000; mydb=# select pg_size_pretty(pg_relation_size('testfragement'));pg_size_pretty --- 651 MB (1 row) ...
/* RELSEG_SIZE is the maximum number of blocks allowed in one disk file. Thus, the maximum size of a single file is RELSEG_SIZE * BLCKSZ; relations bigger than that are divided into multiple files. RELSEG_SIZE * BLCKSZ must be less than your OS' limit on file size. This is often...
index_size - Checks the size of indexes only. last_analyze - Check the maximum time in seconds since any one table has been analyzed. last_autoanalyze - Check the maximum time in seconds since any one table has been autoanalyzed. last_autovacuum - Check the maximum time in seconds since ...
// List all databases using \l+ with more details (including description, tablespace & DB size) (psql) Help on CREATE DATABASE command syntax \h CREATE DATABASE Copy // Help on SQL Command Syntax (For e.g. CREATE DATABASE) (psql) Create database CREATE DATABASE mytest; Copy /...
_series(1,1e6::int) i;INSERT01000000test=#INSERTINTOvarchar_checkSELECTi::base36::text,ifromgenerate_series(1,1e6::int) i;INSERT01000000test=#SELECTpg_size_pretty(pg_table_size('base36_check'))as"base36 size", pg_size_pretty(pg_table_size('varchar_check'))as"varchar_check size";...
checkpoint_timeout代表执行checkout的间隔时间。 max_wal_size和min_wal_size控制wal日志的大小。 # - Archiving - archive_mode = off # enables archiving; off, on, or always # (change requires restart) #archive_command = 'cp $p /var/lib/postgresql/archive/%f' # command to use to archive a...
您可能首先注意到的是,special 与pagesize 相同,这只是表明此页面没有特殊数据部分。特殊数据部分仅用于其他类型的页面,如索引,存储二叉树结构的信息。 您可能想知道为什么所有 checksum 值都为 0。事实证明,Postgres 出于性能考虑,默认情况下会禁用校验和保护,您必须手动启用它。 如果我们比较这些页面的 lower 和 upp...
RELSEG_SIZE requires an initdb. */ #defineRELSEG_SIZE 131072 存储管理器 在Postgres 中,在对表文件管理和操作时,提供了存储管理器(SMGR)的抽象,由于历史原因,早期的系统中,可能存在不同的存储系统,比如磁盘(magnetic disk)、索尼光盘(Sony WORM optical disk jukebox)、持久化主存(persistent main memory)等。
7.CheckPointWarning:如果产生的wal日志超过max_wal_size而导致的检查点发生的时间比这段时间更近,向服务器日志中写入消息,此时建议增加max_wal_size。以下截图取自postgresql 14-internal 代码分析:checkpoint可以由checkpointer进程周期创建,也可以因为其他原因(backend、xlogwrite、shutdown等)通过RequestCheckpoint创建,...