MIO_close Subroutine

The following is the information found in the diagnostic output file. It contains debug information:

• If you set the stats option of the trace module (trace/stats), it runs diagnostics from the trace module.
• If you set the stats option of the pf module (pf/stats), it runs diagnostics from the pf module.
• If you set the stats option of the recov module (recov/stats), it runs diagnostics from the recovery trace.
• If you set the nostats option of the trace or the pf module, these diagnostics are suppressed.

To separate the trace, pf or recov module diagnostics from other outputs, set the stats options to the following other file names:

• trace/stats=<tracefile>
• pf/stats=<pffile>
• recov/stats=<recovfile>

The tracefile, pffile and recovfile are templates for the file names of module diagnostics output. You can give file names for the output of the trace, pf or recov module diagnostics.

Header, which contains the following information:

• Date
• Hostname
• Enabled or disabled AIO
• Program name
• MIO library version
• Environment variables

Debug, which contains the following information:

• The list of all the debug options
• The table of all of the modules' definitions if the DEF debug option is set
• Open request made to the MIO_open64 subroutine if the OPEN debug option is set
• The modules invoked if the MODULES debug option is set

Trace module diagnostic, which contains the following information:

• Time if the TIMESTAMP debug option is set
• Trace on close or on intermediate interrupt
• Trace module position in module_list
• Processed file name
• Rate, which is the amount of data divided by the total time. The total time here means the cumulative amount of time spent beneath the trace module
• Demand rate, which is the amount of data divided by the length of time when the file is opened (including the time of opening and closing the file)
• The current (when tracing) file size and the maximum size of the file during this file processing
• File system information: file type and sector size
• Open mode and flags of the file
• For each subroutine, the following information is displayed:
  name of the subroutine
  count of calling of this subroutine
  time of processing for this subroutine
• For read or write subroutines, the following information is displayed:

  requested (requested size to read or write) total (real size read or write: returned by AIX(r) system call) min (minimum size to read or write) max (maximum size to read or write)

• For the seek subroutine, the following information is displayed:
  the average seek delta (total seek delta/seek count)
• For the aread or awrite subroutine:

  count, time and rate of transfer time including suspend, and read or write time

• For the fcntl subroutine, the number of pages is returned.

date

Trace oncloseor intermediate: 
previous module or calling program<->next module:file name:
(total transferred bytes/total time)=rate
  demand rate=rate/s=total transferred bytes/(close time-open time)
  current size=actual size of the file
max_size=max size of the file
mode=file open mode
FileSystemType=file system type given by fststat(stat_b.f_vfstype)
sector size=Minimum direct i/o transfer size
oflags=file open flags
open    open count     open time
fcntl   fcntl count    fcntl time
read    read count     read time  requested size    total size   minimum    maximum 
aread   aread count    aread time requested size    total size   minimum    maximum
suspend count time rate
write   write count    write time  requested size   total size   minimum    maximum
seek    seek count     seek time   average seek delta
size
page    fcntl page_info count 

MIO statistics file : Tue May 10 14:14:08 2005 
hostname=host1  : with Legacy aio available 
Program=example 
MIO library libmio.a 3.0.0.60  
Apr 19 2005 15:08:17 
MIO_INSTALL_PATH= 
MIO_STATS       =example.stats 
MIO_DEBUG       =OPEN 
MIO_FILES       = *.dat [ trace/stats ] 
MIO_DEFAULTS    = trace/kbytes  

MIO_DEBUG OPEN =T  

Opening file file.dat
    modules[11]=trace/stats 
============================================================================  
Trace close : program <-> aix : file.dat : (4800/0.04)=111538.02 kbytes/s
      demand rate=42280.91 kbytes/s=4800/(0.12-0.01))
      current size=0   max_size=1600
   mode =0640  FileSystemType=JFS sector size=4096
   oflags =0x302=RDWR  CREAT  TRUNC
   open              1     0.00
   write           100     0.02      1600     1600     16384     16384
   read            200     0.02      3200     3200     16384     16384
   seek            101     0.01 average seek delta=-48503
   fcntl             1     0.00
   trunc             1     0.01
   close             1     0.00
   size            100 
============================================================================ 

The following is explanation of the terms in the pf module template:

• nb_pg_compute= number of page compute by cache_size/ page size
• nb_real_pg_not_pf= real number page not prefetch because of pffw option (suppress number of page prefetch because sector not valid)
• nb_pg_not_pf= page of unused prefetch
• nb_unused_pf= number of started prefetch
• nb_pg_to_pf= number of page to prefetch

pf close for /home/user1/pthread/258/SM20182_0.SCR300
50 pages of 2097152 bytes 131072 bytes per sector
133/133 pages not preread for write
23 unused prefetches out of 242 : prefetch=2
95 write behinds
mbytes transferred / Number of requests
program --> 257/257 --> pf --> 257/131 --> aix
program <-- 269/269 <-- pf <-- 265/133 <-- aix

If open or write routine failed, the recov module, if set, is called. The recov module adds the following comments in the output file:

• The value of the open_command option
• The value of the command option
• The errno
• The index of retry

15:30:00
   recov : command=ls -l file=file.dat errno=28 try=0
   recov : failure : new_ret=-1