OMP2012 Frequently asked questions

Last updated: $Date: 2012-10-12 11:22:05 -0400 (Fri, 12 Oct 2012) $ by $Author: BrianWhitney $

This document has frequently asked technical questions and answers. The latest version of this document may be found at http://www.spec.org/omp2012/Docs/faq.html.

If you are looking for the list of known problems with SPEC OMP2012, please see http://www.spec.org/omp2012/Docs/errata.html.

Contents

Requirements

Require.01 How much memory do I need?

Require.02 Does this work with Windows?

Installation

Install.01 ./install.sh: /bin/sh: bad interpreter: Permission denied

Install.02 The DVD drive is on system A, but I want to install on system B. What do I do?

Install.03 Error occurred while processing: C:\Documents

Install.04 How do I uninstall?

Install.05 Do I need to be root?

runspec

runspec.01 Can't locate strict.pm

runspec.02 specperl: bad interpreter: No such file or directory

runspec.03 Do I need to be root?

Building benchmarks

Build.01 CreateProcess((null), ifort ...) failed.

Build.02 make.clean.err does not exist

Build.03 Why is it rebuilding the benchmarks?

Setting up

Setup.01 hash doesn't match after copy

Setup.02 Copying executable failed

Running benchmarks

Run.01 Why does this benchmark take so long to run?

Run.02 Why was there this cryptic message from the operating system?

Miscompares

Miscompare.01 I got a message about a miscompare

Miscompare.02 The benchmark took less than 1 second

Miscompare.03 The .mis file says "short"

Miscompare.04 My compiler is generating bad code!

Miscompare.05 The code is bad even with low optimization!

Miscompare.06 The .mis file is just a bunch of numbers.

Results reporting

Results.01 Where did the reference times go?

Results.02 It's hard to cut/paste into my spreadsheet

Results.03 What is a "flags file"? What does Unknown Flags mean?

Results.04 Submission Check -> FAILED

Power

Power.01 What is the power component of SPEC OMP2012?

Power.02 Am I required to run power?

Power.03 How do I measure power?

Power.04 What kind of power analyzer do I need?

Power.05 Is is possible to get all of the power sample data?

Power.06 What settings are required for the power analyzer?

Power.07 Can I use autoranging?

Power.08 The runspec command caused uncertainty errors, what can I do?

Power.09Can I use more than one power analyzer?

Temperature

Temperature.01I got an error about it being too cold, what can I do?

Requirements

Require.01 q. How much memory do I need?

a. The system requirements may be found in the document system-requirements.html. Currently, the minimum amount of memory in a system to run has been 32 GB.

Require.02 q. Does this work with Windows?

a. The SPEC OMP2012 suite has been tested on a number of platforms, but Windows is not one of them. Because of how this benchmark shares components with SPEC CPU benchmarks, it is possible that it might work on Windows. If you buy this benchmark and expect it to work on Windows, SPEC will not be able to support you because it is not a supported operating system.

Installation

Install.01 q. Why am I getting a message such as "./install.sh: /bin/sh: bad interpreter: Permission denied"?

a. If you are installing from the DVD, check to be sure that your operating system allows programs to be executed from the DVD. For example, some Linux man pages for mount suggest setting the properties for the CD or DVD drive in /etc/fstab to "/dev/cdrom /cd iso9660 ro,user,noauto,unhide", which is notably missing the property "exec". Add exec to that list in /etc/fstab, or add it to your mount command. Notice that the sample Linux mount command in install-guide-unix.html does include exec.

Perhaps install.sh lacks permission to run because you tried to copy all the files from the DVD, in order to move them to another system. If so, please don't do that. There's an easier way. See the next question.

Install.02 q. The DVD drive is on system A, but I want to install on system B. What do I do?

a. The installation guides have an appendix just for you, which describe installing from the network or installing from a tarfile. See Appendix 1 in install-guide-unix.html or install-guide-windows.html.

Install.03 q. Why did the installation fail with Error occurred while processing: C:\Documents?

I was installing on Windows using the tar file. It said:

C:\Documents and Settings\John\omp2012> install
The environment variable SPEC should point to the source of the
SPEC distribution as an absolute path.  I will now try to set
the variable for you...

SPEC is set to C:\Documents and Settings\John\omp2012
If this is NOT what you want, press control-C
Press any key to continue . . .
Installing from "C:\Documents and Settings\John\omp2012"

Checking the integrity of your source tree...

 Depending on the amount of memory in your system, and the speed of your
 destination disk, this may take more than 10 minutes.
 Please be patient.

The system cannot find the file specified.
Error occurred while processing: C:\Documents.
The system cannot find the file specified.
Error occurred while processing: and.
The system cannot find the path specified.
C:\Documents and Settings\John\omp2012\tools\bin\windows-i386\specmd5sum: MANIFEST.tmp: no properly formatted MD5 checksum lines found
Package integrity check failed!
Installation NOT completed!

a. Even though Windows is not a supported OS for SPEC OMP2012, it is possible that things will work. The problem is that the SPEC tools do NOT support spaces in path names. This is a limitation of the SPEC toolset and there are currently no plans to change this requirement. Please use a path that does not contain spaces.

Install.04 q. How do I uninstall? This script uninstall.sh doesn't seem to be it.

a. You are correct that uninstall.sh does not remove the whole product; it only removes the SPEC tool set, and does not affect the benchmarks (which consume the bulk of the disk space). At this time, SPEC does not provide an uninstall utility for the suite as a whole. But it's easy to do: on Unix systems, use rm -Rf on the directory where you installed the suite, for example:

  rm -Rf /home/cs3000/saturos/spec/omp2012

On Windows systems, select the top directory in Windows Explorer and delete it.

If you have been using the output_root feature, you will have to track those down separately. See the suggested commands in the appendix about uninstalling, in the install guides.

Note: instead of deleting the entire directory tree, some users find it useful to keep the config and result subdirectories, while deleting everything else.

Install.05 Do I need to be root?

Occasionally, users of Unix systems have asked whether it is necessary to elevate privileges, or to become 'root', prior to installing or running SPEC OMP2012.

a. SPEC recommends (*) that you do not become root, because: (1) To the best of SPEC's knowledge, no component of SPEC OMP needs to modify system directories, nor does any component need to call privileged system interfaces. (2) Therefore, if you find that it appears that there is some reason why you need to be root, the cause is likely to be outside the SPEC toolset - for example, disk protections, or quota limits. (3) For safe benchmarking, it is better to avoid being root, for the same reason that it is a good idea to wear seat belts in a car: accidents happen, humans make mistakes. For example, if you accidentally type:

kill 1

when you meant to say:

kill %1

then you will very grateful if you are not privileged at that moment.

(*) This is only a recommendation, not a requirement nor a rule.

runspec

runspec.01 q. When I say runspec, why does it say Can't locate strict.pm? For example:

D:\omp2012>runspec --help
Can't locate strict.pm in @INC (@INC contains: .) at
D:\omp2012\bin\runspec line 62.
BEGIN failed--compilation aborted at D:\omp2012\bin\runspec line 62.

a. You can't use runspec if its path is not set correctly. On Unix, Linux, or Mac OS X, you should source shrc or cshrc, as described in runspec.html section 2.4. For Windows, please edit shrc.bat and make the adjustments described in the comments. Then, execute that file, as described in runspec.html section 2.5.

runspec.02 q. Why am I getting messages about specperl: bad interpreter? For example:

bash: /omp2012newdir/bin/runspec: /omp2012/bin/specperl: bad interpreter: No such file or directory

a. Did you move the directory where runspec was installed? If so, you can probably put everything to rights, just by going to the new top of the directory tree and typing "bin/relocate".

For example, the following unwise sequence of events is repaired after completion of the final line.

Top of SPEC benchmark tree is '/omp2012'
Everything looks okay.  cd to /omp2012,
source the shrc file and have at it!
$ cd /omp2012
$ . ./shrc
$ cd ..
$ mv omp2012 omp2012newdir
$ runspec -h | head
bash: runspec: command not found
$ cd omp2012newdir/
$ . ./shrc
$ runspec --help | head
bash: /omp2012newdir/bin/runspec: /omp2012/bin/specperl: bad interpreter: No such file or directory
$ bin/relocate

runspec.03 Do I need to be root?

Regarding the root account, the answer for runspec is the same as the answer for installation question #5, above.

Building benchmarks

Build.01 q. I'm using Windows and I can't build any benchmarks. What does CreateProcess((null), ifort ...) failed mean? For example:

Error with make 'specmake build': check file
'D:/omp2012/benchspec/OMP2012/350.md/run/build_base_omp2012.win32.fast.exe.0000/make.err'
  Error with make!
*** Error building 350.md
-----
make.err:
process_begin: CreateProcess((null), ifort -c -Foblock_solver.obj -Ox block_solver.f, ...) failed.
make (e=2): The system cannot find the file specified.

specmake: *** [block_solver.obj] Error 2     

a. Please note that Windows is not an officially supported platform (see system-requirements.html). It may be possible that Windows will work, so this answer may be of use to you.

This CreateProcess failure occurs on Windows when specmake cannot find your compiler. (Recall from system-requirements.html that the benchmarks are supplied in source code form, and that they must be compiled.)

The reason that it cannot find your compiler is, most likely, because:

  1. You have not edited shrc.bat to correctly reference your compiler, or
  2. You have used a config file that references a compiler that does not exist.

To fix your problem, investigate and address both items.

  1. In shrc.bat, you need to either:

    1. Reference a vendor-supplied file that sets the path.

      The supplied shrc.bat in V1.0 mentions sample .bat files that are often provided by compilers to set your environment. If you want to use this option but you can't find the right file, check your compiler documentation, or you might try searching your hard drive for *vars*bat.

      The file names change frequently; check your compiler docs.

      For example, for Visual Studio 10, you might use something like call "C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\Tools\vsvars32.bat" but for older compilers, you might need to look for vcvars32.bat, not vsvars32.bat.

      For example, when using the (mid-2011) Intel compiler, to select 32 or 64-bit mode, you must remember to add the appropriate argument after the call. This statement requests 32-bit mode:
      call "C:\Program Files (x86)\Intel\ComposerXE-2011\bin\compilervars.bat" ia32

      For example, when using the PGI 11.7 compiler, the path varies depending on whether you are using 32 or 64-bit mode:
      call "c:\Program Files\PGI\win64\11.7\pgi_env.bat"
      or
      call "c:\Program Files (x86)\PGI\win32\11.7\pgi_env.bat"

      Summary: your call statement will vary, by compiler, by version, and sometimes, by features. Check your compiler's documentation, to find the right call.

    2. Or, edit the path yourself.

      You can set the path yourself if you like, with commands such as:

      set PATH=%PATH%;"c:\program files\path\to\my\compiler\bin"

      If you want to use option b, but you can't figure out what path to set, try looking in the documentation for your compiler under topics such as "setting the path", or "command line", or "environment variables". The documentation should mention whether any other environment variables (such as LIB or INCLUDE) are required, in addition to PATH.

  2. You must also use a config file that is appropriate for your compiler.

Build.02 q. The file make.clean.err is mentioned, but it does not exist. Why not?

The tools print a message such as:

   Building 350.md ref base omp2012.win32.fast.exe default:
(build_base_omp2012.win32.fast.exe.0000)
Error with make.clean 'specmake clean': check file
'D:/omp2012/benchspec/CPU2006/350.md/run/build_base_omp2012fast.exe.0000/make.clean.err'
*** Error building 350.md
If you wish to ignore this error, please use '-I' or ignore errors.

But on investigation, the file make.clean.err does not exist. Why not?

a. Please note that Windows is not an officially supported platform (see system-requirements.html). It may be possible that Windows will work, so this answer may be of use to you.

A missing .err file has been reported on Microsoft Windows if a path from shrc.bat uses quoted strings that include semicolons within the quotes, such as:

set PATH="%PATH%;d:\My Compiler Path\bin"  <--- wrong
set PATH="%PATH%;d:\mycompiler\bin"        <--- wrong

Paths such as the above may appear to work if you enter them at the command line. But when the tools call CreateProcess, they cause mysterious-seeming failures. The correct way to do it is:

    set PATH=%PATH%;"d:\My Compiler Path\bin" 
or
    set PATH=%PATH%;d:\mycompiler\bin     

Notice that in both cases, there are no semicolons inside of quotes.

Build.03 q. Why is it rebuilding the benchmarks?

a. You changed something, and the tools thought that it might affect the generated binaries.

Setting up

Setup.01 q. What does hash doesn't match after copy mean?

I got this strange, difficult to reproduce message:
    hash doesn't match after copy ... in copy_file (1 try total)! Sleeping 2 seconds...
followed by several more tries and sleeps. Why?

a. During benchmark setup, certain files are checked. If they don't match what they are expected to, you might see this message. Check:

If the condition persists, try turning up the verbosity level. Look at the files with other tools; do they exist? Can you see differences? Try a different disk and controller. And, check for the specific instance of this message described in the next question.

Setup.02q. Why does it say ERROR: Copying executable failed?

I got this strange, difficult to reproduce message:
    ERROR: Copying executable to run directory FAILED
or
    ERROR: Copying executable from build dir to exe dir FAILED!
along with the bit about hashes not matching from the previous question. Why?

a. Perhaps you have attempted to build the same benchmark twice in two simultaneous jobs.

On most operating systems, the SPEC tools don't mind concurrent jobs. They use your operating system's locking facilities to write the correct outputs to the correct files, even if you fire off many runspec commands at the same time.

But there's one case of simultaneous building that is difficult for the tools to defend against: please don't try to build the very same executable from two different jobs at the same time. Notice that if you say something like this:

$ tail myconfig.cfg
350.md=peak:
basepeak=yes
$ runspec --config myconfig --size test --tune base 350.md &
$ runspec --config myconfig --size test --tune peak 350.md &

then you are trying to build the same benchmark twice in two different jobs, because of the presence of basepeak=yes. Please don't try to do that.

Running benchmarks

Run.01 q. Why does this benchmark suite take so long to run?

a. Please understand that the suite has been designed to be useful for at least 5 years. Benchmarks that seem slow today probably will not seem slow at the end of life of the suite.

Run.02 q. Why was there this cryptic message from the operating system?

a. If you are getting cryptic, hard-to-reproduce, unpredictable error messages from your system, one possible reason may be that the benchmarks consume substantial resources, of several types. If an OS runs out of some resource - for example, pagefile space, or process heap space - it might not give you a very clear message. Instead, you might see only a very brief message, or a diaolog box with a hex error code in it. Please see the hints and suggestions in the section about resources in system-requirements.html.

Miscompares

Miscompare.01 I got a message about a miscompare. The tools said something like:

Running Benchmarks
  Running 358.botsalgn ref base 12.3 default threads:128
/spec/omp2012/21/bin/specinvoke -d /spec/omp2012/21/benchspec/OMP2012/358.
botsalgn/run/run_base_ref_12.3.0000 -e speccmds.err -o speccmds.stdout -f 
speccmds.cmd -C -q
/spec/omp2012/21/bin/specinvoke -E -d /spec/omp2012/21/benchspec/OMP2012/3
58.botsalgn/run/run_base_ref_12.3.0000 -c 1 -e compare.err -o compare.stdo
ut -f compare.cmd -k

*** Miscompare of botsalgn.out; for details see
    /spec/omp2012/21/benchspec/OMP2012/358.botsalgn/run/run_base_ref_12.3.
0000/botsalgn.out.mis
Error: 1x358.botsalgn
Producing Raw Reports
mach: default
  ext: 12.3
    size: ref
      set: gross

Why did it say that? What's the problem?

a. We don't know. Many things can cause a benchmark to miscompare, so we really can't tell you exactly what's wrong based only on the fact that a miscompare occurred.

But don't panic.

Please notice, if you read the message carefully, that there's a suggestion of a very specific file to look in. It may be a little hard to read if you have a narrow terminal window, as in the example above, but if you look carefully you'll see that it says:

*** Miscompare of botsalgn.out; for details see
    /spec/omp2012/21/benchspec/OMP2012/358.botsalgn/run/run_base_ref_12.3.0000/botsalgn.out.mis

Now's the time to look inside that file. Simply doing so may provide a clue as to the nature of your problem.

On Unix systems, change your current directory to the run directory using the path mentioned in the message, for example:

cd /spec/omp2012/21/benchspec/OMP2012/358.botsalgn/run/run_base_ref_12.3.0000

On Microsoft Windows systems, remember to turn the slashes backwards in your cd command.

Then, have a look at the file that was mentioned, using your favorite text editor. If the file does not exist, then check your paths, and check to see whether you have run out of disk space.

Miscompare.02 The benchmark ran, but it took less than 1 second and there was a miscompare. Help!

a. If the benchmark took less than 1 second to execute, it didn't execute properly. There should be one or more .err files in the run directory which will contain some clues about why the benchmark failed to run. Common causes include libraries that were used for compilation but not available during the run, executables that crash with access violations or other exceptions, and permissions problems. See also the suggestions in the next question.

Miscompare.03 I looked in the .mis file and it said something like:

   'rand.234923.out' short

What does "short" mean?

a. If a line like the above is the only line in the .mis file, it means that the benchmark failed to produce any output. In this case, the corresponding error file (look for files with .err extensions in the run directory) may have a clue. In this case, it was Segmentation Fault - core dumped. For problems like this, the first things to examine are the portability flags used to build the benchmark.

Have a look at the sample config files in $SPEC/config or, on Windows, %SPEC%\config. If you constructed your own config file based on one of those, maybe you picked a starting point that was not really appropriate (e.g. you picked a 32-bit config file but are using 64-bit compilation options). Have a look at other samples in that directory. Check at www.spec.org/omp2012 to see if there have been any result submissions using the platform that you are trying to test. If so, compare your portability flags to the ones in the the config files for those results.

If the portability flags are okay, your compiler may be generating bad code.

Miscompare.04 My compiler is generating bad code! Help!

a. Try reducing the optimization that the compiler is doing. Instructions for doing this will vary from compiler to compiler, so it's best to ask your compiler vendor for advice if you can't figure out how to do it for yourself.

Miscompare.05 My compiler is generating bad code with low or no optimization! Help!

a. If you're using a beta compiler, try dropping down to the last released version, or get a newer copy of the beta. If you're using a version of GCC that shipped with your OS, you may want to try getting a "vanilla" (no patches) version and building it yourself.

Miscompare.06 I looked in the .mis file and it was just full of a bunch of numbers.

a. In this case, the benchmark is probably running, but it's not generating answers that are within the tolerances set. See the suggestions for how to deal with compilers that generate bad code in the previous two questions. In particular, you might see if there is a way to encourage your compiler to be careful about optimization of floating point expressions.

Results reporting

Results.01 q. Where did the reference times go?

I was reading an HTML (or PDF or PS) report and see that in the table SPEC now prints all three observations as both seconds and ratio, with the bold underlined item for the median. Although this is useful, CPU2000 results reports included the reference times in their own column, and I miss them. Yes, I understand that the ratio is defined as reference time / observed time, so I could calculate the reference times by simple multiplication. Nevertheless, it was nice having them handy in the previous report format.

a. Because of space issues, the reference times are no longer available in the actual reports. They can be found by examining the reftime files in the data/ref directories of the individual benchmarks. They are also provided in the table below

          350.md             4630
          351.bwaves         4530
          352.nab            3890
          357.bt331          4740
          358.botsalgn       4350
          359.botsspar       5250
          360.ilbdc          3560
          362.fma3d          3800
          363.swim           4530
          367.imagick        7030
          370.mgrid331       4420
          371.applu331       6060
          372.smithwa        5360
          376.kdtree         4500

Results.02 q. It's hard to cut/paste into my spreadsheet

a. Please don't do that. With OMP2012, there's a handy .csv format file right next to the other result formats on the index page. Or, you can go up to the top of your browser and change the .pdf (or .whichever) to .csv

Results.03 q. What is a "flags file"? What does the message Unknown Flags mean in a report?

a. SPEC OMP2012 provides benchmarks in source code form, which are compiled under control of SPEC's toolset. Compilation flags (such as -O5 or -unroll) are detected and reported by the tools with the help of flag description files. Therefore, to do a complete run, you need to (1) point to an existing flags file (easy) or (2) modify an existing flags file (slightly harder) or (3) write one from scratch (definitely harder).

  1. Find an existing flags file by noticing the address of the .xml file at the bottom of any result published at www.spec.org/omp2012. You can use the --flagsurl switch to point your own runspec command at that file, or you can reference it from your config file with the flagsurl option. For example:
       runspec --config=myconfig --flagsurl=http://www.spec.org/omp2012/flags/sun-studio.xml int
  2. You can download the .xml flags file referenced at the bottom of any published result at www.spec.org/omp2012. Warning: clicking on the .xml link may just confuse your web browser; it's probably better to use whatever methods your browser provides to download a file without viewing it - for example, control-click in Safari, right click in Internet Explorer. Then, look at it with a text editor.
  3. You can write your own flags file by following the instructions in flag-description.html.

Notice that you do not need to re-run your tests if the only problem was Unknown flags. You can just use runspec --rawformat --flagsurl

Results.04 q. What's all this about Submission Check -> FAILED littering my log file and my screen?

At the end of my run, why did it print something like this?

format: Submission Check -> FAILED.  Found the following errors:
        - The "hw_memory" field is invalid.
            It must contain leading digits, followed by a space,
            and a standard unit abbreviation.  Acceptable
            abbreviations are KB, MB, GB, and TB.
           The current value is "20480 Megabytes".

a. A complete, reportable result has various information filled in for readers. These fields are listed in the table of contents for config.html. If you wish to submit a result to SPEC for publication at www.spec.org/omp2012, these fields not only have to be filled in; they also have to follow certain formats. Although you are not required to submit your result to SPEC, for convenience the tools try to tell you as much as they can about how the result should be improved if you were to submit it. In the above example, the tools would stop complaining if the field hw_memory said something like "20 GB" instead of "20480 Megabytes".

Notice that you can repair minor formatting problems such as these without doing a re-run of your tests. You are allowed to edit the rawfile, as described in utility.html.

Power

Power.01 q. What is the power component of SPEC OMP2012?

a. As part of the the update to the SPEC OMP benchmark suite, a power measurement component was added. This optional feature allows the power consumed during the benchmark to be reported.

Power.02 q. Am I required to run power?

a. The measurement of power is optional. It requires a methology that SPEC has been developing starting with the SPECpower_ssj2008 benchmark.

Power.03 q. How do I measure power?

a. Please see the runrules as a starting point for what is required to run and measure power. In order to create a submittable run, you will need an approved power analyzer which has been calibrated within the past year by an appropriate testing organization. You will have to connect your system up to the power analyzer. You will need to use the provided tools and set up your configuration file to tell it how to use power. Another place to look for help in how to set up your configuration file is in published OMP2012 results at www.spec.org.

Power.04 q. What kind of power analyzer do I need?

a. Please see the list of accepted power analyzers. The list contains those power analyzers that can be used for making reportable runs.

Power.05 q. Is it possible to retrieve all of the sample data collected from the power analyzer?

a. Power data is sampled at 1 second intervals. This data is stored in the created raw file (.rsf) that is created after a run finishes. As an example, to extract the data, you would run

The output will go to the screen.

The general format of the command is

Where the section will look something like

where <benchmark> is the full benchmark name, <iter> is the iteration number (3 digits).

Power.06 q. What settings are required for the power analyzer?

a. For instructions how to setup the power analyzers and to run the SPEC PTDaemon please consult the SPECpower Measurement Setup Guide which you can find in the PTDaemon tree.

Power.07 q. Can I use autoranging?

a. In order to minimize measurement errors, the autoranging feature should not be used. If the measurement range is too great for your power analyzer for a benchmark run, you can set your measurement rang on a per-benchmark basis. Please check the config.html document for more on how to set the per-benchmark controls.

Power.08 q. The runspec command caused uncertainty errors, what can I do?

a. There could be lots of answers. Are the values being returned during the run within the measurement capabilities that have been set for your power analyzer? Maybe you need to set the range on a per benchmark basis.

If that isn't the problem, you probably need to see if PTDaemon is reporting any errors. If you did not enable PTDaemon with logging, consider restarting it and adding the -l file1 and -d file2 options to capture more information. These may lead you to finding the answer.

Power.09 q. Can I use more than one power analyzer?

a. Yes, it is possible to use more than one power analyzer. Just provide the information in the configuration file to tell the benchmarks which connections to check for the power analyzers.

Temperature

Temperature.01 q. I got an error about it being too cold, what can I do?

ERROR: Minimum temperature during the run (19.5 degC) is less than the minimum a llowed (20 degC)

a. The benchmark requires that the minimum inflow temperature be at 20 degC or higher. This value was chosen to prevent artificially good result by trying to influence the performance of the machine by keeping it colder than normal. To get a submission quality result, you will need to find a warmer spot in your data center to do your runs.

 


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