27.4. Progress Reporting
  
   PostgreSQL
  
  has the ability to report the progress of
   certain commands during command execution.  Currently, the only commands
   which support progress reporting are
  
   CREATE INDEX
  
  ,
  
   VACUUM
  
  and
  
   CLUSTER
  
  . This may be expanded in the future.
 
27.4.1. CREATE INDEX Progress Reporting
   Whenever
   
    CREATE INDEX
   
   or
   
    REINDEX
   
   is running, the
   
    pg_stat_progress_create_index
   
   view will contain
   one row for each backend that is currently creating indexes.  The tables
   below describe the information that will be reported and provide information
   about how to interpret it.
  
    
     Table 27.22. 
     
      pg_stat_progress_create_index
     
     View
    
   
| Column | Type | Description | 
|---|---|---|
| 
         pid
         | 
         integer
         | Process ID of backend. | 
| 
         datid
         | 
         oid
         | OID of the database to which this backend is connected. | 
| 
         datname
         | 
         name
         | Name of the database to which this backend is connected. | 
| 
         relid
         | 
         oid
         | OID of the table on which the index is being created. | 
| 
         index_relid
         | 
         oid
         | OID of the index being created or reindexed.  During a
      non-concurrent 
         CREATE INDEX
        , this is 0. | 
| 
         command
         | 
         text
         | The command that is running: 
         CREATE INDEX
        ,
         CREATE INDEX CONCURRENTLY
        ,
         REINDEX
        , or
         REINDEX CONCURRENTLY
        . | 
| 
         phase
         | 
         text
         | Current processing phase of index creation. See Table 27.23 . | 
| 
         lockers_total
         | 
         bigint
         | Total number of lockers to wait for, when applicable. | 
| 
         lockers_done
         | 
         bigint
         | Number of lockers already waited for. | 
| 
         current_locker_pid
         | 
         bigint
         | Process ID of the locker currently being waited for. | 
| 
         blocks_total
         | 
         bigint
         | Total number of blocks to be processed in the current phase. | 
| 
         blocks_done
         | 
         bigint
         | Number of blocks already processed in the current phase. | 
| 
         tuples_total
         | 
         bigint
         | Total number of tuples to be processed in the current phase. | 
| 
         tuples_done
         | 
         bigint
         | Number of tuples already processed in the current phase. | 
| 
         partitions_total
         | 
         bigint
         | When creating an index on a partitioned table, this column is set to the total number of partitions on which the index is to be created. | 
| 
         partitions_done
         | 
         bigint
         | When creating an index on a partitioned table, this column is set to the number of partitions on which the index has been completed. | 
Table 27.23. CREATE INDEX Phases
| Phase | Description | 
|---|---|
| 
         initializing
         | 
         CREATE INDEX
        or
         REINDEX
        is preparing to create the index.  This
       phase is expected to be very brief. | 
| 
         waiting for writers before build
         | 
         CREATE INDEX CONCURRENTLY
        or
         REINDEX CONCURRENTLY
        is waiting for transactions
       with write locks that can potentially see the table to finish.
       This phase is skipped when not in concurrent mode.
       Columns
         lockers_total
        ,
         lockers_done
        and
         current_locker_pid
        contain the progress
       information for this phase. | 
| 
         building index
         | The index is being built by the access method-specific code.  In this phase,
       access methods that support progress reporting fill in their own progress data,
       and the subphase is indicated in this column.  Typically, 
         blocks_total
        and
         blocks_done
        will contain progress data, as well as potentially
         tuples_total
        and
         tuples_done
        . | 
| 
         waiting for writers before validation
         | 
         CREATE INDEX CONCURRENTLY
        or
         REINDEX CONCURRENTLY
        is waiting for transactions
       with write locks that can potentially write into the table to finish.
       This phase is skipped when not in concurrent mode.
       Columns
         lockers_total
        ,
         lockers_done
        and
         current_locker_pid
        contain the progress
       information for this phase. | 
| 
         index validation: scanning index
         | 
         CREATE INDEX CONCURRENTLY
        is scanning the index searching
       for tuples that need to be validated.
       This phase is skipped when not in concurrent mode.
       Columns
         blocks_total
        (set to the total size of the index)
       and
         blocks_done
        contain the progress information for this phase. | 
| 
         index validation: sorting tuples
         | 
         CREATE INDEX CONCURRENTLY
        is sorting the output of the
       index scanning phase. | 
| 
         index validation: scanning table
         | 
         CREATE INDEX CONCURRENTLY
        is scanning the table
       to validate the index tuples collected in the previous two phases.
       This phase is skipped when not in concurrent mode.
       Columns
         blocks_total
        (set to the total size of the table)
       and
         blocks_done
        contain the progress information for this phase. | 
| 
         waiting for old snapshots
         | 
         CREATE INDEX CONCURRENTLY
        or
         REINDEX CONCURRENTLY
        is waiting for transactions
       that can potentially see the table to release their snapshots.  This
       phase is skipped when not in concurrent mode.
       Columns
         lockers_total
        ,
         lockers_done
        and
         current_locker_pid
        contain the progress
       information for this phase. | 
| 
         waiting for readers before marking dead
         | 
         REINDEX CONCURRENTLY
        is waiting for transactions
       with read locks on the table to finish, before marking the old index dead.
       This phase is skipped when not in concurrent mode.
       Columns
         lockers_total
        ,
         lockers_done
        and
         current_locker_pid
        contain the progress
       information for this phase. | 
| 
         waiting for readers before dropping
         | 
         REINDEX CONCURRENTLY
        is waiting for transactions
       with read locks on the table to finish, before dropping the old index.
       This phase is skipped when not in concurrent mode.
       Columns
         lockers_total
        ,
         lockers_done
        and
         current_locker_pid
        contain the progress
       information for this phase. | 
27.4.2. VACUUM Progress Reporting
   Whenever
   
    VACUUM
   
   is running, the
   
    pg_stat_progress_vacuum
   
   view will contain
   one row for each backend (including autovacuum worker processes) that is
   currently vacuuming.  The tables below describe the information
   that will be reported and provide information about how to interpret it.
   Progress for
   
    VACUUM FULL
   
   commands is reported via
   
    pg_stat_progress_cluster
   
   because both
   
    VACUUM FULL
   
   and
   
    CLUSTER
   
   rewrite the table, while regular
   
    VACUUM
   
   only modifies it
   in place. See
   
    Section 27.4.3
   
   .
  
    
     Table 27.24. 
     
      pg_stat_progress_vacuum
     
     View
    
   
| Column | Type | Description | 
|---|---|---|
| 
         pid
         | 
         integer
         | Process ID of backend. | 
| 
         datid
         | 
         oid
         | OID of the database to which this backend is connected. | 
| 
         datname
         | 
         name
         | Name of the database to which this backend is connected. | 
| 
         relid
         | 
         oid
         | OID of the table being vacuumed. | 
| 
         phase
         | 
         text
         | Current processing phase of vacuum. See Table 27.25 . | 
| 
         heap_blks_total
         | 
         bigint
         | Total number of heap blocks in the table.  This number is reported
       as of the beginning of the scan; blocks added later will not be (and
       need not be) visited by this 
         VACUUM
        . | 
| 
         heap_blks_scanned
         | 
         bigint
         | Number of heap blocks scanned.  Because the
        
         visibility map
        
        is used to optimize scans,
       some blocks will be skipped without inspection; skipped blocks are
       included in this total, so that this number will eventually become
       equal to 
         heap_blks_total
        when the vacuum is complete.
       This counter only advances when the phase is
         scanning heap
        . | 
| 
         heap_blks_vacuumed
         | 
         bigint
         | Number of heap blocks vacuumed.  Unless the table has no indexes, this
       counter only advances when the phase is 
         vacuuming heap
        .
       Blocks that contain no dead tuples are skipped, so the counter may
       sometimes skip forward in large increments. | 
| 
         index_vacuum_count
         | 
         bigint
         | Number of completed index vacuum cycles. | 
| 
         max_dead_tuples
         | 
         bigint
         | Number of dead tuples that we can store before needing to perform an index vacuum cycle, based on maintenance_work_mem . | 
| 
         num_dead_tuples
         | 
         bigint
         | Number of dead tuples collected since the last index vacuum cycle. | 
Table 27.25. VACUUM Phases
| Phase | Description | 
|---|---|
| 
         initializing
         | 
         VACUUM
        is preparing to begin scanning the heap.  This
       phase is expected to be very brief. | 
| 
         scanning heap
         | 
         VACUUM
        is currently scanning the heap.  It will prune and
       defragment each page if required, and possibly perform freezing
       activity.  The
         heap_blks_scanned
        column can be used
       to monitor the progress of the scan. | 
| 
         vacuuming indexes
         | 
         VACUUM
        is currently vacuuming the indexes.  If a table has
       any indexes, this will happen at least once per vacuum, after the heap
       has been completely scanned.  It may happen multiple times per vacuum
       if
        
         maintenance_work_mem
        
        (or, in the case of autovacuum,
        
         autovacuum_work_mem
        
        if set) is insufficient to store
       the number of dead tuples found. | 
| 
         vacuuming heap
         | 
         VACUUM
        is currently vacuuming the heap.  Vacuuming the heap
       is distinct from scanning the heap, and occurs after each instance of
       vacuuming indexes.  If
         heap_blks_scanned
        is less than
         heap_blks_total
        , the system will return to scanning
       the heap after this phase is completed; otherwise, it will begin
       cleaning up indexes after this phase is completed. | 
| 
         cleaning up indexes
         | 
         VACUUM
        is currently cleaning up indexes.  This occurs after
       the heap has been completely scanned and all vacuuming of the indexes
       and the heap has been completed. | 
| 
         truncating heap
         | 
         VACUUM
        is currently truncating the heap so as to return
       empty pages at the end of the relation to the operating system.  This
       occurs after cleaning up indexes. | 
| 
         performing final cleanup
         | 
         VACUUM
        is performing final cleanup.  During this phase,
         VACUUM
        will vacuum the free space map, update statistics
       in
         pg_class
        , and report statistics to the statistics
       collector.  When this phase is completed,
         VACUUM
        will end. | 
27.4.3. CLUSTER Progress Reporting
   Whenever
   
    CLUSTER
   
   or
   
    VACUUM FULL
   
   is
   running, the
   
    pg_stat_progress_cluster
   
   view will
   contain a row for each backend that is currently running either command.
   The tables below describe the information that will be reported and
   provide information about how to interpret it.
  
    
     Table 27.26. 
     
      pg_stat_progress_cluster
     
     View
    
   
| Column | Type | Description | 
|---|---|---|
| 
         pid
         | 
         integer
         | Process ID of backend. | 
| 
         datid
         | 
         oid
         | OID of the database to which this backend is connected. | 
| 
         datname
         | 
         name
         | Name of the database to which this backend is connected. | 
| 
         relid
         | 
         oid
         | OID of the table being clustered. | 
| 
         command
         | 
         text
         | The command that is running. Either 
         CLUSTER
        or
         VACUUM FULL
        . | 
| 
         phase
         | 
         text
         | Current processing phase. See Table 27.27 . | 
| 
         cluster_index_relid
         | 
         oid
         | If the table is being scanned using an index, this is the OID of the index being used; otherwise, it is zero. | 
| 
         heap_tuples_scanned
         | 
         bigint
         | Number of heap tuples scanned.
       This counter only advances when the phase is 
         seq scanning heap
        ,
         index scanning heap
        or
         writing new heap
        . | 
| 
         heap_tuples_written
         | 
         bigint
         | Number of heap tuples written.
       This counter only advances when the phase is 
         seq scanning heap
        ,
         index scanning heap
        or
         writing new heap
        . | 
| 
         heap_blks_total
         | 
         bigint
         | Total number of heap blocks in the table.  This number is reported
       as of the beginning of 
         seq scanning heap
        . | 
| 
         heap_blks_scanned
         | 
         bigint
         | Number of heap blocks scanned.  This counter only advances when the
       phase is 
         seq scanning heap
        . | 
| 
         index_rebuild_count
         | 
         bigint
         | Number of indexes rebuilt.  This counter only advances when the phase
       is 
         rebuilding index
        . | 
Table 27.27. CLUSTER and VACUUM FULL Phases
| Phase | Description | 
|---|---|
| 
         initializing
         | The command is preparing to begin scanning the heap. This phase is expected to be very brief. | 
| 
         seq scanning heap
         | The command is currently scanning the table using a sequential scan. | 
| 
         index scanning heap
         | 
         CLUSTER
        is currently scanning the table using an index scan. | 
| 
         sorting tuples
         | 
         CLUSTER
        is currently sorting tuples. | 
| 
         writing new heap
         | 
         CLUSTER
        is currently writing the new heap. | 
| 
         swapping relation files
         | The command is currently swapping newly-built files into place. | 
| 
         rebuilding index
         | The command is currently rebuilding an index. | 
| 
         performing final cleanup
         | The command is performing final cleanup.  When this phase is
       completed, 
         CLUSTER
        or
         VACUUM FULL
        will end. |