Can't link '(file-path)' to '(link-path)'

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Contents 1 General 2 Version Information 3 Example Log(s) 3.1 Can't Link '(file-path)' To '(link-path)' 3.2 Unexpected Process State 7 4 Other Related Messages 5 Developer Information

[edit] General

Message Type: Error Message

This Message means that the BOINC Client Software was in the process of starting the execution of a Work Unit. During the start up process, it tried to "link" (connect) the actual executable Science Application to the "Slots Directory" by creating a symbolic link file in the "Slots Directory".

[edit] Version Information

• None.

[edit] Example Log(s)

[edit] Can't Link '(file-path)' To '(link-path)'

In this specific example, the Error Code is -108 which indicates a write permissions problem. So, the most likely cause of the problem is a "permissions" error on the indicated directory. In this case the directory "0" in the "Slots Directory" may have incorrect permissions set. For example, an improper shut-down operation may have "scrambled" the permissions so write to the directory is denied.

(01) 2005-08-21 11:41:51 [SETI@home] Started download of 17au03ab.19262.23072.534674.111
(02) 2005-08-21 11:41:54 [SETI@home] Finished download of 17au03ab.19262.23072.534674.111
(03) 2005-08-21 11:41:54 [SETI@home] Throughput 122575 bytes/sec
(04) 2005-08-21 11:41:57 [         ] request_reschedule_cpus: files downloaded
(05) 2005-08-21 11:42:00 [SETI@home] Can't link
                                     projects/setiathome.berkeley.edu/setiathome_4.18_windows_intelx86.exe to
                                      slots/0/setiathome_4.18_windows_intelx86.exe
(06) 2005-08-21 11:42:00 [SETI@home] Unrecoverable error for result
                                     17au03ab.19262.23072.534674.111_3
                                     (Couldn't start or resume: -108)
(07) 2005-08-21 11:42:00 [         ] request_reschedule_cpus: start failed
(08) 2005-08-21 11:42:00 [SETI@home] Deferring communication with project for 56 seconds
(09) 2005-08-21 11:42:00 [SETI@home] Computation for result 17au03ab.19262.23072.534674.111_3 finished
(10) 2005-08-21 11:42:21 [         ] request_reschedule_cpus: project op
(11) 2005-08-21 11:42:21 [SETI@home] Sending scheduler request to
                                     http://setiboinc.ssl.berkeley.edu/sah_cgi/cgi
(12) 2005-08-21 11:42:21 [SETI@home] Requesting 8640 seconds of work, returning 1 results
(13) 2005-08-21 11:42:22 [SETI@home] Scheduler request to
                                     http://setiboinc.ssl.berkeley.edu/sah_cgi/cgi succeeded

Line-By-Line Explanation

1. Started download of '(file)'
   • This message indicates the "File Name" of the file that is to be downloaded, and that the download operation has been started.
2. Finished download of '(file)'
   • This message indicates that the file has completed the download operation.
3. Throughput 'x' bytes/sec
   • This message indicates the measured speed of the file transfer.
4. request_reschedule_cpus: files downloaded
   • This message indicates that the Work Scheduler needs to re-examine the current schedule to see if it needs to be changed based on the fact that the contents of the Work Buffer has been changed.
5. Can't link '(file-path)' to '(link-path)'
   • The BOINC Daemon was not able to make a "symbolic-link" between the Slots Directory and the executable file for the Science Application.
6. Unrecoverable error for result '(result)' (Couldn't start or resume: '(error-code)')
   • The start-up process for a Work Unit/Result failed. In this case because the link could not be made between the Slots Directory and the Science Application.
7. request_reschedule_cpus: start failed
   • The CPU is still idle because the start failed so we need to find it some work ... idle hands are the devil's workshop ... or so I have been told.
8. Deferring communication with project for "z" seconds
   • It was too early to contact the Project's Scheduler again, so a pause.
9. Computation for result '(result)' finished
   • Because of the error, we are done with the Result.
10. request_reschedule_cpus: project op
    • With a Scheduler Request in process, we "schedule" the CPUs.
11. Sending scheduler request to '(url)'
    • We need more work... so ...
12. Requesting '(seconds)' seconds of work, returning '(count)' results
    • We are going to ask for more work, and return the one Result.
13. Scheduler request to '(url)' succeeded
    • And we had a successful exchange between this Participant's Computer and the Project's Scheduler.

[edit] Unexpected Process State 7

In this example, the fundamental problem is the inability to link the Work Unit/Result to the Science Application. In the midst of this turmoil, there arose a small timing issue which caused the BOINC Daemon to register an "Unexpected Process State".

(01) 2005-10-08 06:39:07 [SETI@home] Sending scheduler request to
                                     http://setiboinc.ssl.berkeley.edu/sah_cgi/cgi
(02) 2005-10-08 06:39:07 [SETI@home] Requesting 8640 seconds of work, returning 1 results
(03) 2005-10-08 06:39:08 [SETI@home] Scheduler request to  
                                     http://setiboinc.ssl.berkeley.edu/sah_cgi/cgi succeeded
(04) 2005-10-08 06:39:09 [SETI@home] Started download of 09oc03ab.7118.10257.529844.98
(05) 2005-10-08 06:39:11 [SETI@home] Finished download of 09oc03ab.7118.10257.529844.98
(06) 2005-10-08 06:39:11 [SETI@home] Throughput 420295 bytes/sec
(07) 2005-10-08 06:39:11 [         ] request_reschedule_cpus: files downloaded
(08) 2005-10-08 06:39:11 [SETI@home] Can't link
                                     projects/setiathome.berkeley.edu/setiathome_4.18_windows_intelx86.exe
                                     to slots/0/setiathome_4.18_windows_intelx86.exe
(09) 2005-10-08 06:39:11 [SETI@home] Unrecoverable error for result
                                     09oc03ab.7118.10257.529844.98_1 (Couldn't start or resume: -108)
(10) 2005-10-08 06:39:11 [         ] request_reschedule_cpus: start failed
(11) 2005-10-08 06:39:11 [SETI@home] resume_or_start(): unexpected process state 7
(12) 2005-10-08 06:39:12 [SETI@home] Deferring communication with project for 10 minutes and 2 seconds
(13) 2005-10-08 06:39:12 [SETI@home] Computation for result 09oc03ab.7118.10257.529844.98_1 finished
(14) 2005-10-08 06:49:15 [SETI@home] Sending scheduler request to  
                                     http://setiboinc.ssl.berkeley.edu/sah_cgi/cgi
(15) 2005-10-08 06:49:15 [SETI@home] Requesting 8640 seconds of work, returning 1 results
(16) 2005-10-08 06:49:16 [SETI@home] Scheduler request to  
                                     http://setiboinc.ssl.berkeley.edu/sah_cgi/cgi succeeded

Line-By-Line Explanation

1. Sending scheduler request to '(url)'
   • In this log we have a request to the Project's Scheduler.
2. Requesting '(seconds)' seconds of work, returning '(count)' results
   • Within the Scheduler Request Message we are asking for work to the tune of 'x' seconds, and also returning 'count' Results to the Project. In this case, there was a need for a small amount of additional work, so the time was set to 8,640 seconds worth of work needed; and there are one Result to "report".
3. Scheduler request to '(url)' succeeded
   • And in this case we had success! We also will be downloading one new Work Unit ...
4. Started download of '(file)'
   • This message indicates the "File Name" of the file that is to be downloaded, and that the download operation has been started.
5. Finished download of '(file)'
   • This message indicates that the file has completed the download operation.
6. Throughput 'x' bytes/sec
   • This message indicates the measured speed of the file transfer.
7. request_reschedule_cpus: files downloaded
   • This message indicates that the Work Scheduler needs to re-examine the current schedule to see if it needs to be changed based on the fact that the contents of the Work Buffer has been changed.
8. Can't link '(file-path)' to '(link-path)'
   • The BOINC Daemon was not able to make a "symbolic-link" between the Slots Directory and the executable file for the Science Application.
9. Unrecoverable error for result '(result)' (Couldn't start or resume: '(error-code)')
   • The start-up process for a Work Unit/Result failed. In this case because the link could not be made between the Slots Directory and the Science Application.
10. request_reschedule_cpus: start failed
    • The CPU is still idle because the start failed so we need to find it some work.
11. resume_or_start(): unexpected process state '(process-state)'
    • The BOINC Daemon has detected an unexpected process state, basically that when it looked at the process it should have been "running" or "exited", but it was found in "Couldn't Start" (basically a timing issue).
12. Deferring communication with project for "z" seconds
    • It was too early to contact the Project's Scheduler again, so a pause.
13. Computation for result '(result)' finished
    • Because of the error, we are done with the Result, but now we need more work ...
14. Sending scheduler request to '(url)'
    • We send again, a new Scheduler Request Message to the Project's Scheduler.
15. Requesting '(seconds)' seconds of work, returning '(count)' results
    • Within the Scheduler Request Message we are asking for work to the tune of 'x' seconds, and also returning 'count' Results to the Project. In this case, there was a need for a small amount of additional work, so the time was set to 8,640 seconds worth of work needed; and there are one Result to "report".
16. Scheduler request to '(url)' succeeded
    • And we can move on ...

[edit] Other Related Messages

• Can't copy '(file-path)' to '(link-path)'

[edit] Developer Information

Code Location:	boinc/client/app_start.C
Function:	setup_file(WORKUNIT* wup, FILE_INFO* fip, FILE_REF& fref, char* file_path, char* slot_dir)
Documentation:	boinc/client/app_start.C
CVS Extract:	cvs -d :pserver:anonymous:@alien.ssl.berkeley.edu:/home/cvs/cvsroot checkout boinc/client/app_start.C