as less latency than 4KB. I was looking for explanation of this behavior but did not get any. 1. MPIR_CVAR_CH3_EAGER_MAX_MSG_SIZE is set to 128KB. So none of the abov= e message size is using Rendezvous protocol. Is there any partition inside = eager protocol (e.g. 0 - 512 bytes, 1KB - 8KB, 16KB - 64KB)? If yes then wh= at are the boundaries for them? Can I log them with debug-event-logging? Setup I am using: - two nodes has intel core i7, one with 16gb memory another one 8gb - mpich 3.2.1, configured and build to use nemesis tcp - 1gb Ethernet connection - NFS is using for sharing - osu_latency: uses MPI_Send and MPI_Recv - MPIR_CVAR_CH3_EAGER_MAX_MSG_SIZE=3D 131072 (128KB) Can anyone help me on that? Thanks in advance. Best Regards, Abu Naser _______________________________________________ discuss mailing list [email protected]<mailto: [email protected]> To manage subscription options or unsubscribe: https: //lists.mpich.org/mailman/listinfo/discuss -- Jeff Hammond [email protected]<mailto: [email protected]> http: //jeffhammond.github.io/ _______________________________________________ discuss mailing list [email protected]<mailto: [email protected]> To manage subscription options or unsubscribe: https: //lists.mpich.org/mailman/listinfo/discuss --_000_BLUPR0501MB2003EB7C1C3701600F398E4997770BLUPR0501MB2003_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <html><head> <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Diso-8859-= 1"> <style type=3D"text/css" style=3D"display: none;"><!-- P {margin-top:0;margi= n-bottom: 0;} --></style> </head> <body dir=3D"ltr"> <div id=3D"divtagdefaultwrapper" style=3D"font-size: 12pt;color:#000000;font= -family: Calibri,Helvetica,sans-serif;" dir=3D"ltr"> <div id=3D"divtagdefaultwrapper" style=3D"font-size: 12pt; color: rgb(0, 0,= 0); font-family: Calibri, Helvetica, sans-serif, "EmojiFont", &q= uot;Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, &q= uot;Segoe UI Symbol", "Android Emoji", EmojiSymbols;" dir=3D= "ltr"> <p style=3D"margin-top: 0;margin-bottom:0">Hello Min,</p> <p style=3D"margin-top: 0;margin-bottom:0"><br> </p> <p style=3D"margin-top: 0;margin-bottom:0">Thanks for the clarification.&nbs= p; I will do the experiment.<br> </p> <p style=3D"margin-top: 0;margin-bottom:0"><br> </p> <div id=3D"Signature"> <div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size: 12pt; color= : rgb(0,0,0); font-family:Calibri,Helvetica,sans-serif,"EmojiFont"= ,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,&q= uot;Segoe UI Symbol","Android Emoji",EmojiSymbols"> <p>Thanks.</p> <p align=3D"left"><span style=3D"font-size: 10pt; font-family:Calibri,Helvet= ica,sans-serif">Best Regards,</span></p> <span style=3D"font-family: Calibri,Helvetica,sans-serif; font-size:10pt"></= span> <div align=3D"left"><span style=3D"font-size: 11pt; font-family:Calibri,Helv= etica,sans-serif"></span></div> <span style=3D"font-family: Calibri,Helvetica,sans-serif; font-size:10pt"></= span> <p align=3D"left"><span style=3D"font-size: 10pt; font-family:Calibri,Helvet= ica,sans-serif">Abu Naser</span><br> </p> </div> </div> </div> <hr style=3D"display: inline-block;width:98%" tabindex=3D"-1"> <div id=3D"divRplyFwdMsg" dir=3D"ltr"><font style=3D"font-size: 11pt" face= =3D"Calibri, sans-serif" color=3D"#000000"><b>From: </b> Min Si <msi@anl.= gov><br> <b>Sent: </b> Wednesday, June 20, 2018 1:39:30 PM<br> <b>To: </b> [email protected]<br> <b>Subject: </b> Re: [mpich-discuss] osu_latency test: why 8KB takes less ti= me than 4KB and 2KB takes less time than 1KB?</font> <div> </div> </div> <meta content=3D"text/html; charset=3DWindows-1252"> <div style=3D"background-color: #FFFFFF">Hi Abu,<br> <br> I think Jeff means that you should run your experiment with more iterations= in order to get a stable results.<br> - Increase the iteration of for loop in each execution (I think osu benchma= rk allows you to set it)<br> - Run the experiments 10 or 100 times, and take the average and standard de= viation.<br> <br> If you see a very small standard deviation (e.g., <=3D5%), then the tren= d is stable and you might not see such gaps.<br> <br> Best regards,<br> Min<br> <div class=3D"x_moz-cite-prefix">On 2018/06/20 12: 14, Abu Naser wrote:<br> </div> <blockquote type=3D"cite"> <div id=3D"x_divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size: 12pt; co= lor: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif, "Emoji= Font", "Apple Color Emoji", "Segoe UI Emoji", Noto= ColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSy= mbols;"> <p style=3D"margin-top: 0; margin-bottom:0">Hello Jeff,</p> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <p style=3D"margin-top: 0; margin-bottom:0">Yes, I am using a switch and oth= er machines are also connected with that switch. <br> </p> <p style=3D"margin-top: 0; margin-bottom:0">If I remove other machines and j= ust use my two node with the switch, then will it improve the performance b= y 200 ~ 400 iterations?</p> <p style=3D"margin-top: 0; margin-bottom:0">Meanwhile I will give a try with= a single dedicated cable. <span></span><br> </p> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <p style=3D"margin-top: 0; margin-bottom:0">Thank you.<br> </p> <div id=3D"x_Signature"> <div id=3D"x_divtagdefaultwrapper" dir=3D"ltr" style=3D""> <p><br> </p> <p align=3D"left"><span style=3D"font-size: 10pt; font-family:Calibri,Helvet= ica,sans-serif">Best Regards,</span></p> <span style=3D"font-family: Calibri,Helvetica,sans-serif; font-size:10pt"></= span> <div align=3D"left"><span style=3D"font-size: 11pt; font-family:Calibri,Helv= etica,sans-serif"></span></div> <span style=3D"font-family: Calibri,Helvetica,sans-serif; font-size:10pt"></= span> <p align=3D"left"><span style=3D"font-size: 10pt; font-family:Calibri,Helvet= ica,sans-serif">Abu Naser</span><br> </p> </div> </div> </div> <hr tabindex=3D"-1" style=3D"display: inline-block; width:98%"> <div id=3D"x_divRplyFwdMsg" dir=3D"ltr"><font style=3D"font-size: 11pt" face= =3D"Calibri, sans-serif" color=3D"#000000"><b>From: </b> Jeff Hammond <a class=3D"x_moz-txt-link-rfc2396E OWAAutoLink" href=3D"mailto: jeff.scienc= [email protected]" id=3D"LPlnk983157" previewremoved=3D"true"> <[email protected]></a><br> <b>Sent: </b> Wednesday, June 20, 2018 12:52:06 PM<br> <b>To: </b> MPICH<br> <b>Subject: </b> Re: [mpich-discuss] osu_latency test: why 8KB takes less ti= me than 4KB and 2KB takes less time than 1KB?</font> <div> </div> </div> <meta content=3D"text/html; charset=3Dutf-8"> <div> <div dir=3D"ltr">Is the ethernet connection a single dedicated cable betwee= n the two machines or are you running through a switch that handles other t= raffic? <div><br> </div> <div>My best guess is that this is noise and that you may be able to avoid = it by running a very long time, e.g. 10000 iterations.</div> <div><br> </div> <div>Jeff</div> </div> <div class=3D"x_x_gmail_extra"><br> <div class=3D"x_x_gmail_quote">On Wed, Jun 20, 2018 at 6: 53 AM, Abu Naser <= span dir=3D"ltr"> <<a href=3D"mailto: [email protected]" target=3D"_blank" id=3D"LPlnk305789= " class=3D"OWAAutoLink" previewremoved=3D"true">[email protected]</a>></s= pan> wrote: <br> <blockquote class=3D"x_x_gmail_quote" style=3D"margin: 0 0 0 .8ex; border-le= ft: 1px #ccc solid; padding-left:1ex"> <div dir=3D"ltr"> <div id=3D"x_x_m_6077755676379859201divtagdefaultwrapper" dir=3D"ltr" style= =3D""> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <p style=3D"margin-top: 0; margin-bottom:0">Good day to all,</p> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <p style=3D"margin-top: 0; margin-bottom:0">I had run point to point osu_lat= ency test in two nodes for 200 times. Followings are the average time= in microsecond for various size of the messages -</p> <div>1KB 84.8514 us<br> <span style=3D"color: rgb(255,0,0)">2KB 73.52535</span> us= <br> 4KB 272.55275 us<br> <span style=3D"color: rgb(255,0,0)">8KB 234.86385</span> u= s<br> 16KB 288.88 us<br> 32KB 523.3725 us<br> 64KB 910.4025 us</div> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <p style=3D"margin-top: 0; margin-bottom:0">From the above looks like, 2KB m= essage has less latency than 1 KB and 8KB has less latency than 4KB. <br> </p> <p style=3D"margin-top: 0; margin-bottom:0">I was looking for explanation of= this behavior but did not get any.</p> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <ol style=3D"margin-bottom: 0px; margin-top:0px"> <li><span>MPIR_CVAR_CH3_EAGER_MAX_MSG_<wbr>SIZE</span><span> is set to 128K= B. So none of the above message size is using Rendezvous protocol. Is there= any partition inside eager protocol (e.g. 0 - 512 bytes, 1KB - 8KB, 16KB -= 64KB)? If yes then what are the boundaries for them? Can I log them with debug-event-logging? </span><br> </li></ol> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <p style=3D"margin-top: 0; margin-bottom:0">Setup I am using:</p> <p style=3D"margin-top: 0; margin-bottom:0">- two nodes has intel core i7, o= ne with 16gb memory another one 8gb</p> <p style=3D"margin-top: 0; margin-bottom:0">- mpich 3.2.1, configured and bu= ild to use nemesis tcp</p> <p style=3D"margin-top: 0; margin-bottom:0">- 1gb Ethernet connection</p> <p style=3D"margin-top: 0; margin-bottom:0">- NFS is using for sharing<br> </p> <p style=3D"margin-top: 0; margin-bottom:0">- osu_latency : uses MPI_Send an= d MPI_Recv</p> <p style=3D"margin-top: 0; margin-bottom:0">- <span>MPIR_CVAR_CH3_EAGER_MAX_= MSG_<wbr>SIZE</span>=3D <span>131072</span> (128KB)<br> </p> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <p style=3D"margin-top: 0; margin-bottom:0">Can anyone help me on that? Than= ks in advance.<br> </p> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <p style=3D"margin-top: 0; margin-bottom:0"><br> </p> <div id=3D"x_x_m_6077755676379859201Signature"> <div id=3D"x_x_m_6077755676379859201divtagdefaultwrapper" dir=3D"ltr" style= =3D""> <p><br> </p> <p align=3D"left"><span style=3D"font-size: 10pt; font-family:Calibri,Helvet= ica,sans-serif">Best Regards,</span></p> <span style=3D"font-family: Calibri,Helvetica,sans-serif; font-size:10pt"></= span> <div align=3D"left"><span style=3D"font-size: 11pt; font-family:Calibri,Helv= etica,sans-serif"></span></div> <span style=3D"font-family: Calibri,Helvetica,sans-serif; font-size:10pt"></= span> <p align=3D"left"><span style=3D"font-size: 10pt; font-family:Calibri,Helvet= ica,sans-serif">Abu Naser</span><br> </p> </div> </div> </div> </div> <br> ______________________________<wbr>_________________<br> discuss mailing list <a href=3D"mailto: [email protected]= " id=3D"LPlnk816471" class=3D"OWAAutoLink" previewremoved=3D"true">discuss@= mpich.org</a><br> To manage subscription options or unsubscribe: <br> <a href=3D"https: //lists.mpich.org/mailman/listinfo/discuss" rel=3D"norefer= rer" target=3D"_blank" id=3D"LPlnk624595" class=3D"OWAAutoLink" previewremo= ved=3D"true">https: //lists.mpich.org/<wbr>mailman/listinfo/discuss</a><br> <br> </blockquote> </div> <br> <br clear=3D"all"> <div><br> </div> -- <br> <div class=3D"x_x_gmail_signature">Jeff Hammond<br> <a href=3D"mailto: [email protected]" target=3D"_blank" id=3D"LPlnk3149= 93" class=3D"OWAAutoLink" previewremoved=3D"true">[email protected]</a=
<br> <a href=3D"http: //jeffhammond.github.io/" target=3D"_blank" id=3D"LPlnk8614= 34" class=3D"OWAAutoLink" previewremoved=3D"true">http: //jeffhammond.github= .io/</a></div> </div> </div> <br> <fieldset class=3D"x_mimeAttachmentHeader"></fieldset> <br> <pre>_______________________________________________=0A= discuss mailing list <a class=3D"x_moz-txt-link-abbreviated OWAAutoLink= " href=3D"mailto: [email protected]" id=3D"LPlnk657371" previewremoved=3D"tr= ue">[email protected]</a>=0A= To manage subscription options or unsubscribe: =0A= <a class=3D"x_moz-txt-link-freetext OWAAutoLink" href=3D"https: //lists.mpic= h.org/mailman/listinfo/discuss" id=3D"LPlnk669988" previewremoved=3D"true">= https: //lists.mpich.org/mailman/listinfo/discuss</a>=0A= </pre> </blockquote> <br> </div> </div> </body> </html>
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