Re: [openib-general] Repost: AIO SDP and ttcp.aio: Event errors
1. OK. That's fair enough. I'll give that ago. 2. Yeah, it also occurs for large values of -n, say 1. 3. Great. 4. Yeah, the times are small as I'm only doing short runs (-n 1000) to avoid the -32/-104 errors. I'll try pushing -n up a bit. Thanks Libor, Steve. Libor Michalek wrote: On Tue, Apr 12, 2005 at 09:08:15PM +0100, Steven Wooding wrote: Hi, I have been putting ttcp.aio through its paces and have a few questions. 1. When -l is larger than 131072 I get an Event error <-22> on the transmit side and no data to transferred. Changing values of -n and -a do not make any difference. The FMRs need to be sized at initialization time. The code currently picks 128K as the size for the FMRs, and does not support an AIO operation that would span multiple FMRs. If you want to try larger AIO operations with the current code you will need to recompile SDP with a larger FMR size, which is determined by the constant SDP_IOCB_SIZE_MAX in sdp_iocb.h It's been a while since I've last tried this, if you try it and have problems let me know. 2. When using a value of 1 for -a (so I suppose this is non-aio), I get an Event error of <-32> on the transmit side and an <-104> on the receiver end. Only some of the data is transferred. I'll look into this, I'm seeing a problem on longer runs myself. With a value of 1 for -a it still uses aio, the value only means how many aio operations can be outstanding at a given time. This just means that a single buffer will be submitted for read/write and a new one will not be submitted until that buffer's IO completes. 3. For future reference, where can I find out what these Event error codes mean to give me a glue of what's going wrong. The errors are errno values. I'll make a note to write up which errors are possible and what they are likely to mean. 4. I sometimes see significant differences in the transfer speed reported on the transmit and receiver ends. Is one more right than the other? Are the wall clock times for the data transfers small, on the order of a few seconds? How big of a wall clock time difference are you seeing? -Libor ___ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
Re: [openib-general] Repost: AIO SDP and ttcp.aio: Event errors
On Tue, Apr 12, 2005 at 09:08:15PM +0100, Steven Wooding wrote: > Hi, > > I have been putting ttcp.aio through its paces and have a few questions. > > 1. When -l is larger than 131072 I get an Event error <-22> on the transmit > side and no data to transferred. Changing values of -n and -a do not make > any difference. The FMRs need to be sized at initialization time. The code currently picks 128K as the size for the FMRs, and does not support an AIO operation that would span multiple FMRs. If you want to try larger AIO operations with the current code you will need to recompile SDP with a larger FMR size, which is determined by the constant SDP_IOCB_SIZE_MAX in sdp_iocb.h It's been a while since I've last tried this, if you try it and have problems let me know. > 2. When using a value of 1 for -a (so I suppose this is non-aio), I get an > Event error of <-32> on the transmit side and an <-104> on the receiver end. > Only some of the data is transferred. I'll look into this, I'm seeing a problem on longer runs myself. With a value of 1 for -a it still uses aio, the value only means how many aio operations can be outstanding at a given time. This just means that a single buffer will be submitted for read/write and a new one will not be submitted until that buffer's IO completes. > 3. For future reference, where can I find out what these Event error codes > mean to give me a glue of what's going wrong. The errors are errno values. I'll make a note to write up which errors are possible and what they are likely to mean. > 4. I sometimes see significant differences in the transfer speed reported on > the transmit and receiver ends. Is one more right than the other? Are the wall clock times for the data transfers small, on the order of a few seconds? How big of a wall clock time difference are you seeing? -Libor ___ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
[openib-general] Repost: AIO SDP and ttcp.aio: Event errors
Hi, I have been putting ttcp.aio through its paces and have a few questions. 1. When -l is larger than 131072 I get an Event error <-22> on the transmit side and no data to transferred. Changing values of -n and -a do not make any difference. 2. When using a value of 1 for -a (so I suppose this is non-aio), I get an Event error of <-32> on the transmit side and an <-104> on the receiver end. Only some of the data is transferred. 3. For future reference, where can I find out what these Event error codes mean to give me a glue of what's going wrong. 4. I sometimes see significant differences in the transfer speed reported on the transmit and receiver ends. Is one more right than the other? My system details are: Two nodes with Dual Xeon 64-bit processors HCA: MT25208 (in MT23108 compat mode) with 128MB of ram OS: RHEL 4 (64-bit) Gen2 stack version: trunk of 2113 (subversion revision number) Thanks, Steve. ___ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
