[Cbc] Two minor issues in cbc (maxtime ...)

Christian Troost Christian.troost at uni-hohenheim.de
Tue Jan 23 01:30:41 EST 2018


Dear all,

just one doubt: From my experience  I guess order of commands is important. So I would say you must set the time limit before you call solve and quit, otherwise it can't be taken into account.

Best,
Christian 

Am 23. Januar 2018 04:02:48 MEZ schrieb cbc-request at coin-or.org:
>Send Cbc mailing list submissions to
>	cbc at list.coin-or.org
>
>To subscribe or unsubscribe via the World Wide Web, visit
>	https://urldefense.proofpoint.com/v2/url?u=https-3A__list.coin-2Dor.org_mailman_listinfo_cbc&d=DwICAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=jf64w96-SZWFoSGL6RvJTCLdjpDrCQsBg5xepU6-I65dM553oHvWvH3QcWawbnI2&m=hHFRhglYWcW5pjXxDEpYqcPTY_8jh9cKG1IwbvPYN-M&s=2h6rQoh4CpU-ejZmABBCkZT5v5jDrP2IeUPB3E5dDds&e=
>
>or, via email, send a message with subject or body 'help' to
>	cbc-request at list.coin-or.org
>
>You can reach the person managing the list at
>	cbc-owner at list.coin-or.org
>
>When replying, please edit your Subject line so it is more specific
>than "Re: Contents of Cbc digest..."
>
>
>Today's Topics:
>
>   1. Re: two minor issues in cbc (maxtime and log) (Matthew Galati)
>   2. Re: two minor issues in cbc (maxtime and log) (Andrew Wald)
>
>
>----------------------------------------------------------------------
>
>Message: 1
>Date: Mon, 22 Jan 2018 21:59:40 -0500
>From: Matthew Galati <matthew.galati at gmail.com>
>To: Andrew Wald <andrewjohnwald at gmail.com>
>Cc: "cbc at list.coin-or.org" <cbc at list.coin-or.org>
>Subject: Re: [Cbc] two minor issues in cbc (maxtime and log)
>Message-ID: <187F90F8-76A1-4BDB-B69A-5B4EC68621B7 at gmail.com>
>Content-Type: text/plain; charset="utf-8"
>
>Wall clock and cpu are pretty close here. I suspect CBC is just not
>checking maxtime often enough (inside some expensive operation). 
>
>Sent from my iPhone
>
>> On Jan 22, 2018, at 9:48 PM, Andrew Wald <andrewjohnwald at gmail.com>
>wrote:
>> 
>> Hi Matthew,
>> 
>> It seems like your problem is pretty large and spent a lot of time
>pre-processing... 
>> 
>> Not sure if this will help since I don't have your files to test, but
>this might be something to try. What about constraining by the wall
>clock like this when you call it up:
>> cbc -solve -quit -seconds 1300 -timeMode elapsed
>> 
>> - Andrew
>> 
>> 
>>> On Mon, Jan 22, 2018 at 8:06 PM, Matthew Galati
><Matthew.Galati at sas.com> wrote:
>>> Two minor issues. This is through the C++ CBCModel API using the
>latest CBC.
>>> 
>>>  
>>> 
>>> I set max time (1300 seconds), but CBC did not stop until after
>19,900 seconds.
>>> This is a maximization problem, but the final summary states ?Lower
>bound? for the bound. It might be cleaner to just say ?bound? ? to
>avoid confusion.
>>>  
>>> 
>>> command line - cbc -solve -quit -seconds 1300 (default strategy 1)
>>> 
>>> Continuous objective value is 1.88508e+09 - 855.75 seconds
>>> 
>>> Cgl0005I 998000 SOS with 13941976 members
>>> 
>>> Cgl0004I processed model has 999000 rows, 13941976 columns (13941976
>integer (13                                                            
>                         941976 of which binary)) and 26887952 elements
>>> 
>>> Cutoff increment increased from 1e-05 to 0.9999
>>> 
>>> Cbc0020I Exiting on maximum time
>>> 
>>> Cbc0005I Partial search - best objective 1e+50 (best possible
>-1.885078e+09), to                                                     
>                         ok 0 iterations and 0 nodes (19624.31 seconds)
>>> 
>>> Cbc0035I Maximum depth 0, 0 variables fixed on reduced cost
>>> 
>>> Cuts at root node changed objective from -1.88508e+09 to
>-1.88508e+09
>>> 
>>> Probing was tried 0 times and created 0 cuts of which 0 were active
>after adding                                                           
>                                      rounds of cuts (0.000 seconds)
>>> 
>>> Gomory was tried 0 times and created 0 cuts of which 0 were active
>after adding                                                           
>                                      rounds of cuts (0.000 seconds)
>>> 
>>> Knapsack was tried 0 times and created 0 cuts of which 0 were active
>after addin                                                            
>                                    g rounds of cuts (0.000 seconds)
>>> 
>>> Clique was tried 0 times and created 0 cuts of which 0 were active
>after adding                                                           
>                                      rounds of cuts (0.000 seconds)
>>> 
>>> MixedIntegerRounding2 was tried 0 times and created 0 cuts of which
>0 were activ                                                           
>                          e after adding rounds of cuts (0.000 seconds)
>>> 
>>> FlowCover was tried 0 times and created 0 cuts of which 0 were
>active after addi                                                      
>                                      ng rounds of cuts (0.000 seconds)
>>> 
>>> TwoMirCuts was tried 0 times and created 0 cuts of which 0 were
>active after add                                                       
>                                     ing rounds of cuts (0.000 seconds)
>>> 
>>>  
>>> 
>>> Result - Stopped on time limit
>>> 
>>>  
>>> 
>>> No feasible solution found
>>> 
>>> Lower bound:                    1885078031.000
>>> 
>>> Enumerated nodes:               0
>>> 
>>> Total iterations:               0
>>> 
>>> Time (CPU seconds):             19928.34
>>> 
>>> Time (Wallclock seconds):       19973.07
>>> 
>>>  
>>> 
>>> Total time (CPU seconds):       19930.87   (Wallclock seconds):     
> 19975.64
>>> 
>>> 
>>> _______________________________________________
>>> Cbc mailing list
>>> Cbc at list.coin-or.org
>>>
>https://urldefense.proofpoint.com/v2/url?u=https-3A__list.coin-2Dor.org_mailman_listinfo_cbc&d=DwICAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=jf64w96-SZWFoSGL6RvJTCLdjpDrCQsBg5xepU6-I65dM553oHvWvH3QcWawbnI2&m=hHFRhglYWcW5pjXxDEpYqcPTY_8jh9cKG1IwbvPYN-M&s=2h6rQoh4CpU-ejZmABBCkZT5v5jDrP2IeUPB3E5dDds&e=
>
>>> 
>> 
>> _______________________________________________
>> Cbc mailing list
>> Cbc at list.coin-or.org
>>
>https://urldefense.proofpoint.com/v2/url?u=https-3A__list.coin-2Dor.org_mailman_listinfo_cbc&d=DwICAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=jf64w96-SZWFoSGL6RvJTCLdjpDrCQsBg5xepU6-I65dM553oHvWvH3QcWawbnI2&m=hHFRhglYWcW5pjXxDEpYqcPTY_8jh9cKG1IwbvPYN-M&s=2h6rQoh4CpU-ejZmABBCkZT5v5jDrP2IeUPB3E5dDds&e=
>
>-------------- next part --------------
>An HTML attachment was scrubbed...
>URL:
><https://urldefense.proofpoint.com/v2/url?u=http-3A__list.coin-2Dor.org_pipermail_cbc_attachments_20180122_d3cd910f_attachment-2D0001.html&d=DwICAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=jf64w96-SZWFoSGL6RvJTCLdjpDrCQsBg5xepU6-I65dM553oHvWvH3QcWawbnI2&m=hHFRhglYWcW5pjXxDEpYqcPTY_8jh9cKG1IwbvPYN-M&s=qO-mN-dEvKdGuU8NIjn63PMq0rKpfBJK05f2BJF6wYk&e=
>>
>
>------------------------------
>
>Message: 2
>Date: Mon, 22 Jan 2018 21:02:46 -0600
>From: Andrew Wald <andrewjohnwald at gmail.com>
>To: Matthew Galati <matthew.galati at gmail.com>
>Cc: "cbc at list.coin-or.org" <cbc at list.coin-or.org>
>Subject: Re: [Cbc] two minor issues in cbc (maxtime and log)
>Message-ID:
>	<CADbqYTKjknLm8Aq4zz+7tJFsDEdz8Ej2n10J5rmfU-qDgsXH+A at mail.gmail.com>
>Content-Type: text/plain; charset="utf-8"
>
>Yeah I saw they were close, just didn't know if the wallclock was maybe
>checked on a different frequency or perhaps on a separate thread.
>
>On Mon, Jan 22, 2018 at 8:59 PM, Matthew Galati
><matthew.galati at gmail.com>
>wrote:
>
>> Wall clock and cpu are pretty close here. I suspect CBC is just not
>> checking maxtime often enough (inside some expensive operation).
>>
>> Sent from my iPhone
>>
>> On Jan 22, 2018, at 9:48 PM, Andrew Wald <andrewjohnwald at gmail.com>
>wrote:
>>
>> Hi Matthew,
>>
>> It seems like your problem is pretty large and spent a lot of time
>> pre-processing...
>>
>> Not sure if this will help since I don't have your files to test, but
>this
>> might be something to try. What about constraining by the wall clock
>like
>> this when you call it up:
>> cbc -solve -quit -seconds 1300 -timeMode elapsed
>>
>> - Andrew
>>
>>
>> On Mon, Jan 22, 2018 at 8:06 PM, Matthew Galati
><Matthew.Galati at sas.com>
>> wrote:
>>
>>> Two minor issues. This is through the C++ CBCModel API using the
>latest
>>> CBC.
>>>
>>>
>>>
>>>    1. I set max time (1300 seconds), but CBC did not stop until
>after
>>>    19,900 seconds.
>>>    2. This is a maximization problem, but the final summary states
>>>    ?Lower bound? for the bound. It might be cleaner to just say
>?bound? ? to
>>>    avoid confusion.
>>>
>>>
>>>
>>> command line - cbc -solve -quit -seconds 1300 (default strategy 1)
>>>
>>> Continuous objective value is 1.88508e+09 - 855.75 seconds
>>>
>>> Cgl0005I 998000 SOS with 13941976 members
>>>
>>> Cgl0004I processed model has 999000 rows, 13941976 columns (13941976
>>> integer (13
>>>                           941976 of which binary)) and 26887952
>elements
>>>
>>> Cutoff increment increased from 1e-05 to 0.9999
>>>
>>> Cbc0020I Exiting on maximum time
>>>
>>> Cbc0005I Partial search - best objective 1e+50 (best possible
>>> -1.885078e+09), to
>>>                                              ok 0 iterations and 0
>nodes
>>> (19624.31 seconds)
>>>
>>> Cbc0035I Maximum depth 0, 0 variables fixed on reduced cost
>>>
>>> Cuts at root node changed objective from -1.88508e+09 to
>-1.88508e+09
>>>
>>> Probing was tried 0 times and created 0 cuts of which 0 were active
>after
>>> adding
>>>                                             rounds of cuts (0.000
>>> seconds)
>>>
>>> Gomory was tried 0 times and created 0 cuts of which 0 were active
>after
>>> adding
>>>                                             rounds of cuts (0.000
>>> seconds)
>>>
>>> Knapsack was tried 0 times and created 0 cuts of which 0 were active
>>> after addin
>>>                                                 g rounds of cuts
>(0.000
>>> seconds)
>>>
>>> Clique was tried 0 times and created 0 cuts of which 0 were active
>after
>>> adding
>>>                                 rounds of cuts (0.000 seconds)
>>>
>>> MixedIntegerRounding2 was tried 0 times and created 0 cuts of which
>0
>>> were activ
>>>                                           e after adding rounds of
>cuts
>>> (0.000 seconds)
>>>
>>> FlowCover was tried 0 times and created 0 cuts of which 0 were
>active
>>> after addi
>>>                                          ng rounds of cuts (0.000
>>> seconds)
>>>
>>> TwoMirCuts was tried 0 times and created 0 cuts of which 0 were
>active
>>> after add
>>>                                         ing rounds of cuts (0.000
>>> seconds)
>>>
>>>
>>>
>>> Result - Stopped on time limit
>>>
>>>
>>>
>>> No feasible solution found
>>>
>>> Lower bound:                    1885078031.000
>>>
>>> Enumerated nodes:               0
>>>
>>> Total iterations:               0
>>>
>>> Time (CPU seconds):             19928.34
>>>
>>> Time (Wallclock seconds):       19973.07
>>>
>>>
>>>
>>> Total time (CPU seconds):       19930.87   (Wallclock seconds):
>>> 19975.64
>>>
>>> _______________________________________________
>>> Cbc mailing list
>>> Cbc at list.coin-or.org
>>>
>https://urldefense.proofpoint.com/v2/url?u=https-3A__list.coin-2Dor.org_mailman_listinfo_cbc&d=DwICAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=jf64w96-SZWFoSGL6RvJTCLdjpDrCQsBg5xepU6-I65dM553oHvWvH3QcWawbnI2&m=hHFRhglYWcW5pjXxDEpYqcPTY_8jh9cKG1IwbvPYN-M&s=2h6rQoh4CpU-ejZmABBCkZT5v5jDrP2IeUPB3E5dDds&e=
>
>>>
>>>
>> _______________________________________________
>> Cbc mailing list
>> Cbc at list.coin-or.org
>>
>https://urldefense.proofpoint.com/v2/url?u=https-3A__list.coin-2Dor.org_mailman_listinfo_cbc&d=DwICAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=jf64w96-SZWFoSGL6RvJTCLdjpDrCQsBg5xepU6-I65dM553oHvWvH3QcWawbnI2&m=hHFRhglYWcW5pjXxDEpYqcPTY_8jh9cKG1IwbvPYN-M&s=2h6rQoh4CpU-ejZmABBCkZT5v5jDrP2IeUPB3E5dDds&e=
>
>>
>>
>-------------- next part --------------
>An HTML attachment was scrubbed...
>URL:
><https://urldefense.proofpoint.com/v2/url?u=http-3A__list.coin-2Dor.org_pipermail_cbc_attachments_20180122_1dc19dbd_attachment.html&d=DwICAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=jf64w96-SZWFoSGL6RvJTCLdjpDrCQsBg5xepU6-I65dM553oHvWvH3QcWawbnI2&m=hHFRhglYWcW5pjXxDEpYqcPTY_8jh9cKG1IwbvPYN-M&s=v4PPNErBS7KGUbpQRWGM_aoc0F04ouE17wrZnz1ozCQ&e=
>>
>
>------------------------------
>
>Subject: Digest Footer
>
>_______________________________________________
>Cbc mailing list
>Cbc at list.coin-or.org
>https://urldefense.proofpoint.com/v2/url?u=https-3A__list.coin-2Dor.org_mailman_listinfo_cbc&d=DwICAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=jf64w96-SZWFoSGL6RvJTCLdjpDrCQsBg5xepU6-I65dM553oHvWvH3QcWawbnI2&m=hHFRhglYWcW5pjXxDEpYqcPTY_8jh9cKG1IwbvPYN-M&s=2h6rQoh4CpU-ejZmABBCkZT5v5jDrP2IeUPB3E5dDds&e=
>
>
>
>------------------------------
>
>End of Cbc Digest, Vol 125, Issue 15
>************************************

-- 
Diese Nachricht wurde von meinem Android-Gerät mit K-9 Mail gesendet.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/cbc/attachments/20180123/6f6c9792/attachment-0001.html>


More information about the Cbc mailing list