SELECT snap_id
,phyrds
,readtim
,phywrts
,writetim
,wait_count
FROM PERFSTAT.STATS$FILESTATXS

select ts.name      tsname
     , df.name	    filename
     , fs.phyrds
     , fs.phywrts
     , fs.readtim
     , fs.writetim
     , fs.singleblkrds
     , fs.phyblkrd
     , fs.phyblkwrt
     , fs.singleblkrdtim
     , fw.count     wait_count
     , fw.time      time
     , df.file#
  from x$kcbfwait   fw
     , v$filestat   fs
     , v$tablespace ts
     , v$datafile   df
 where ts.ts#    = df.ts#
   and fs.file#  = df.file#
   and fw.indx+1 = df.file#;