June 2024 - discuss - mailman3.cels.anl.gov

Re: [mpich-discuss] Mpich over RDMA sample
by Zhou, Hui 12 Jun '24

12 Jun '24

Niyaz, All you need to do is to set an environment variable `FI_PROVIDER=verbs`. -- Hui Zhou From: Niyaz Murshed <Niyaz.Murshed(a)arm.com> Date: Wednesday, June 12, 2024 at 1:23 PM To: Zhou, Hui <zhouh(a)anl.gov>, discuss(a)mpich.org <discuss(a)mpich.org> Cc: nd <nd(a)arm.com> Subject: Re: Mpich over RDMA sample When testing with Libfabric, verbs provider is selected. I did have to use “-e msg -d mlx5_1” so that it selects verbs. I was checking if there is anything like that for mpich sample tests. Else might need to do some hack in the code to force ZjQcmQRYFpfptBannerStart This Message Is From an External Sender This message came from outside your organization. ZjQcmQRYFpfptBannerEnd When testing with Libfabric, verbs provider is selected. I did have to use “-e msg -d mlx5_1” so that it selects verbs. I was checking if there is anything like that for mpich sample tests. Else might need to do some hack in the code to force the selection of verbs. From: Zhou, Hui <zhouh(a)anl.gov> Date: Wednesday, June 12, 2024 at 1:15 PM To: discuss(a)mpich.org <discuss(a)mpich.org> Cc: Niyaz Murshed <Niyaz.Murshed(a)arm.com>, nd <nd(a)arm.com> Subject: Re: Mpich over RDMA sample Libfabric support multiple providers. Sounds like it was selecting the sockets or tcp provider rather than a provider that support RoCE. I am not exactly sure whether the verbs provider will do that. If you can confirm the provider using libfabric tests, then you can try forcing MPICH to use that provider by setting the FI_PROVIDER environment variable. -- Hui Zhou From: Niyaz Murshed via discuss <discuss(a)mpich.org> Date: Wednesday, June 12, 2024 at 9:03 AM To: discuss(a)mpich.org <discuss(a)mpich.org> Cc: Niyaz Murshed <Niyaz.Murshed(a)arm.com>, nd <nd(a)arm.com> Subject: [mpich-discuss] Mpich over RDMA sample Hello, I am trying to learn about MPICH and its performance over RDMA. I am using libfabric and installed mpich using the below configure. ./configure --prefix=/opt/mpich/ --with-ofi=/opt/libfabric/ When I run any applications between 2 directly ZjQcmQRYFpfptBannerStart This Message Is From an External Sender This message came from outside your organization. ZjQcmQRYFpfptBannerEnd Hello, I am trying to learn about MPICH and its performance over RDMA. I am using libfabric and installed mpich using the below configure. ./configure --prefix=/opt/mpich/ --with-ofi=/opt/libfabric/ When I run any applications between 2 directly connected servers having Mellanox NICs, I see that communication is happening over tcp and not over RoCE. Is there any way to test commination over RoCE ? For eg. I was able to test it for libfabric using the below sample that comes along with libfabric to test RMA. Is there something similar for MPICH ? or use the current sample to use RoCE by some parameter? Server : fi_rma_bw -s 192.168.1.100 -e msg -d mlx5_1 -S 1024 -I 1 Client : fi_rma_bw -s 192.168.1.200 -e msg -d mlx5_3 192.168.1.100 -S 1024 -I 1 Regards, Niyaz

1 0

Re: [mpich-discuss] Mpich over RDMA sample
by Niyaz Murshed 12 Jun '24

12 Jun '24

When testing with Libfabric, verbs provider is selected. I did have to use “-e msg -d mlx5_1” so that it selects verbs. I was checking if there is anything like that for mpich sample tests. Else might need to do some hack in the code to force the selection of verbs. From: Zhou, Hui <zhouh(a)anl.gov> Date: Wednesday, June 12, 2024 at 1:15 PM To: discuss(a)mpich.org <discuss(a)mpich.org> Cc: Niyaz Murshed <Niyaz.Murshed(a)arm.com>, nd <nd(a)arm.com> Subject: Re: Mpich over RDMA sample Libfabric support multiple providers. Sounds like it was selecting the sockets or tcp provider rather than a provider that support RoCE. I am not exactly sure whether the verbs provider will do that. If you can confirm the provider using libfabric tests, then you can try forcing MPICH to use that provider by setting the FI_PROVIDER environment variable. -- Hui Zhou From: Niyaz Murshed via discuss <discuss(a)mpich.org> Date: Wednesday, June 12, 2024 at 9:03 AM To: discuss(a)mpich.org <discuss(a)mpich.org> Cc: Niyaz Murshed <Niyaz.Murshed(a)arm.com>, nd <nd(a)arm.com> Subject: [mpich-discuss] Mpich over RDMA sample Hello, I am trying to learn about MPICH and its performance over RDMA. I am using libfabric and installed mpich using the below configure. ./configure --prefix=/opt/mpich/ --with-ofi=/opt/libfabric/ When I run any applications between 2 directly ZjQcmQRYFpfptBannerStart This Message Is From an External Sender This message came from outside your organization. ZjQcmQRYFpfptBannerEnd Hello, I am trying to learn about MPICH and its performance over RDMA. I am using libfabric and installed mpich using the below configure. ./configure --prefix=/opt/mpich/ --with-ofi=/opt/libfabric/ When I run any applications between 2 directly connected servers having Mellanox NICs, I see that communication is happening over tcp and not over RoCE. Is there any way to test commination over RoCE ? For eg. I was able to test it for libfabric using the below sample that comes along with libfabric to test RMA. Is there something similar for MPICH ? or use the current sample to use RoCE by some parameter? Server : fi_rma_bw -s 192.168.1.100 -e msg -d mlx5_1 -S 1024 -I 1 Client : fi_rma_bw -s 192.168.1.200 -e msg -d mlx5_3 192.168.1.100 -S 1024 -I 1 Regards, Niyaz

1 0

Re: [mpich-discuss] Mpich over RDMA sample
by Zhou, Hui 12 Jun '24

12 Jun '24

Libfabric support multiple providers. Sounds like it was selecting the sockets or tcp provider rather than a provider that support RoCE. I am not exactly sure whether the verbs provider will do that. If you can confirm the provider using libfabric tests, then you can try forcing MPICH to use that provider by setting the FI_PROVIDER environment variable. -- Hui Zhou From: Niyaz Murshed via discuss <discuss(a)mpich.org> Date: Wednesday, June 12, 2024 at 9:03 AM To: discuss(a)mpich.org <discuss(a)mpich.org> Cc: Niyaz Murshed <Niyaz.Murshed(a)arm.com>, nd <nd(a)arm.com> Subject: [mpich-discuss] Mpich over RDMA sample Hello, I am trying to learn about MPICH and its performance over RDMA. I am using libfabric and installed mpich using the below configure. ./configure --prefix=/opt/mpich/ --with-ofi=/opt/libfabric/ When I run any applications between 2 directly ZjQcmQRYFpfptBannerStart This Message Is From an External Sender This message came from outside your organization. ZjQcmQRYFpfptBannerEnd Hello, I am trying to learn about MPICH and its performance over RDMA. I am using libfabric and installed mpich using the below configure. ./configure --prefix=/opt/mpich/ --with-ofi=/opt/libfabric/ When I run any applications between 2 directly connected servers having Mellanox NICs, I see that communication is happening over tcp and not over RoCE. Is there any way to test commination over RoCE ? For eg. I was able to test it for libfabric using the below sample that comes along with libfabric to test RMA. Is there something similar for MPICH ? or use the current sample to use RoCE by some parameter? Server : fi_rma_bw -s 192.168.1.100 -e msg -d mlx5_1 -S 1024 -I 1 Client : fi_rma_bw -s 192.168.1.200 -e msg -d mlx5_3 192.168.1.100 -S 1024 -I 1 Regards, Niyaz

1 0

Mpich over RDMA sample
by Niyaz Murshed 12 Jun '24

12 Jun '24

Hello, I am trying to learn about MPICH and its performance over RDMA. I am using libfabric and installed mpich using the below configure. ./configure --prefix=/opt/mpich/ --with-ofi=/opt/libfabric/ When I run any applications between 2 directly connected servers having Mellanox NICs, I see that communication is happening over tcp and not over RoCE. Is there any way to test commination over RoCE ? For eg. I was able to test it for libfabric using the below sample that comes along with libfabric to test RMA. Is there something similar for MPICH ? or use the current sample to use RoCE by some parameter? Server : fi_rma_bw -s 192.168.1.100 -e msg -d mlx5_1 -S 1024 -I 1 Client : fi_rma_bw -s 192.168.1.200 -e msg -d mlx5_3 192.168.1.100 -S 1024 -I 1 Regards, Niyaz

1 0

Re: [mpich-discuss] Fail on MPI_Wait
by Zhou, Hui 11 Jun '24

11 Jun '24

>MPIDI_OFI_handle_cq_error(793): OFI poll failed (ofi_events.c:793:MPIDI_OFI_handle_cq_error:Input/output error) This is an error coming from the libfabric provider. First we need find out which provider are you using. Try set environment variable MPIR_CVAR_DEBUG_SUMMARY=1 and run a simple MPI_INIT+MPI_Finalize test code. Could post its console output? -- Hui ________________________________ From: Palmer, Bruce J via discuss <discuss(a)mpich.org> Sent: Tuesday, June 11, 2024 3:17 PM To: discuss(a)mpich.org <discuss(a)mpich.org> Cc: Palmer, Bruce J <Bruce.Palmer(a)pnnl.gov> Subject: [mpich-discuss] Fail on MPI_Wait Hi, I’m trying to debug a GPU-aware runtime for the Global Arrays library. We had a version of this working a while ago, but it has mysteriously started failing and we are trying to track down why. Currently, we are getting failures in MPI_Wait ZjQcmQRYFpfptBannerStart This Message Is From an External Sender This message came from outside your organization. ZjQcmQRYFpfptBannerEnd Hi, I’m trying to debug a GPU-aware runtime for the Global Arrays library. We had a version of this working a while ago, but it has mysteriously started failing and we are trying to track down why. Currently, we are getting failures in MPI_Wait and were wondering if anyone could provide some information on what exactly seems to be failing inside the wait call. The error we are getting is Abort(206752655) on node 0: Fatal error in internal_Wait: Other MPI error, error stack: internal_Wait(68205)..........: MPI_Wait(request=0x500847a0, status=0x7ffff9331800) failed MPIR_Wait(780)................: MPIR_Wait_state(737)..........: MPIDI_progress_test(134)......: MPIDI_OFI_handle_cq_error(793): OFI poll failed (ofi_events.c:793:MPIDI_OFI_handle_cq_error:Input/output error) I’ve verified that the handle corresponding to 0x500847a0 is getting set earlier in the code in an MPI_Isend call and that no MPI_Wait or MPI_Test is called on the handle before it crashes with the above error message. I’m using MPICH 4.2.1 using gcc/8.3.0. The MPICH library was configured with ../configure --prefix=/people/d3g293/mpich/mpich-4.2.1/build_newell/install \ --with-device=ch4:ofi:sockets --with-libfabric=embedded \ --without-ucx --enable-threads=multiple --with-slurm \ CC=gcc CXX=g+ I’ve tried building with UCX and gotten the same results. Are these errors indicative of corruption of the request handle or problems with some internal MPI data structures or something else? Any information you can provide would be appreciated. Thanks, Bruce

1 0

Fail on MPI_Wait
by Palmer, Bruce J 11 Jun '24

11 Jun '24

Hi, I’m trying to debug a GPU-aware runtime for the Global Arrays library. We had a version of this working a while ago, but it has mysteriously started failing and we are trying to track down why. Currently, we are getting failures in MPI_Wait and were wondering if anyone could provide some information on what exactly seems to be failing inside the wait call. The error we are getting is Abort(206752655) on node 0: Fatal error in internal_Wait: Other MPI error, error stack: internal_Wait(68205)..........: MPI_Wait(request=0x500847a0, status=0x7ffff9331800) failed MPIR_Wait(780)................: MPIR_Wait_state(737)..........: MPIDI_progress_test(134)......: MPIDI_OFI_handle_cq_error(793): OFI poll failed (ofi_events.c:793:MPIDI_OFI_handle_cq_error:Input/output error) I’ve verified that the handle corresponding to 0x500847a0 is getting set earlier in the code in an MPI_Isend call and that no MPI_Wait or MPI_Test is called on the handle before it crashes with the above error message. I’m using MPICH 4.2.1 using gcc/8.3.0. The MPICH library was configured with ../configure --prefix=/people/d3g293/mpich/mpich-4.2.1/build_newell/install \ --with-device=ch4:ofi:sockets --with-libfabric=embedded \ --without-ucx --enable-threads=multiple --with-slurm \ CC=gcc CXX=g+ I’ve tried building with UCX and gotten the same results. Are these errors indicative of corruption of the request handle or problems with some internal MPI data structures or something else? Any information you can provide would be appreciated. Thanks, Bruce

1 0

Join us Wednesday, June 12th for an MPICH BoF as part of CASS Community BoF Days
by Raffenetti, Ken 10 Jun '24

10 Jun '24

All, The MPICH team will host a Birds-of-a-Feather session this Wednesday, June 12th at 10am Central time as part of the first ever CASS Community BoF Days https://urldefense.us/v3/__https://cass.community/bofs.html__;!!G_uCfscf7eW… . We hope to see folks there to discuss upcoming MPICH release plans and to hear presentations from MPICH users. Date and Time: Wednesday, June 12th, 10:00am – 11:30am Central Time Registration: https://urldefense.us/v3/__https://exascaleproject.zoomgov.com/meeting/regi… Agenda: * Welcome and ANL Update * Welcome – Ken Raffenetti * ANL Update – Yanfei Guo * User Presentations * Jeff Hammond, NVIDIA * Vitali Morozon, ANL * Wei-keng Liao, Northwestern University * Jiajun Huang, ANL/University of California, Riverside * Junchao Zhang, ANL * Q&A Cheers, The MPICH team

1 0

MPI debugging using PTP
by Dr. Yehuda Singer 09 Jun '24

09 Jun '24

Dear Sir/Mrs. I use the Eclipse scientific package. . I develop automatic parallelization. One mode is that we use multiple processors connected in a network. We want that all the cores of each processors will work efficiently on The application. The first stage is to take a 40 cores machine and run the application in groups of 8 cores using MPI. The only way to do it is using the PTP. In any case the Eclipses scientific activates the PTP. There were the following problems in activating the parallel debugger: 1. The script for MPICH2 to start debugging was full with logical errors. I revised it and now it works. I can send it to you. 2. The SDM package which is written in Chas not been maintained. I organized it as an Eclipse C/C++ project and changed definitions which do not follow the C standard. C98 Enclosed please find: 1. The MPI code in C++ 2. Screen snap-shot. Best regards, Yehuda Dr. Yehuda Singer Parallel Solutions Ltd. https://urldefense.us/v3/__http://www.llp.co.il__;!!G_uCfscf7eWS!biR3k0xs8t… <https://urldefense.us/v3/__http://www.llp.co.il/__;!!G_uCfscf7eWS!biR3k0xs8… > Office: 972-74-7012159 Mobile: 972-52-2306-311

1 0