SUMMARY_FILE_IOSTAT

Records the summary of statistics about data file I/Os of each node in the cluster to reflect performance issues such as exceptions in I/O operations, as described in Table 1.

The values of phyrds, phywrts, phyblkrd, phyblkwrt, readtim and writetim are summed up based on the data of each node. avgiotim is the average value (total duration/total times) of each node. lstiotim and maxiowtm are the maximum values of each node. miniotim is the minimum value of each node.

**Table 1** SUMMARY_FILE_IOSTAT columns
Name	Type	Description
filenum	oid	File ID.
dbid	oid	Database ID.
spcid	oid	Tablespace ID.
phyrds	numeric	Number of times of reading physical files.
phywrts	numeric	Number of times of writing into physical files.
phyblkrd	numeric	Number of times of reading physical file blocks.
phyblkwrt	numeric	Number of times of writing into physical file blocks.
readtim	numeric	Total duration of reading (unit: μs).
writetim	numeric	Total duration of writing (unit: μs).
avgiotim	bigint	Average duration of reading and writing (unit: μs).
lstiotim	bigint	Duration of the last file reading (unit: μs).
miniotim	bigint	Minimum duration of reading and writing (unit: μs).
maxiowtm	bigint	Maximum duration of reading and writing (unit: μs).