Re: When is an OSA card too busy?
Jim, I know I've banged on about this before, but I can't stress enough just how useful taking a (SYSTCPDA) packet trace during your problem period (even for just a minute or two), using IPCS to convert it to SNIFFER format, downloading it to a PC and feeding it into Wireshark (www.wireshark.org) for analysis. Alternatively, get Wireshark to capture the OSA traffic on a mirrored switch port - you need to involve your network people for that though. If you do this, Wireshark will show you in glorious color if you have a problem. Some things I'd look for are (in no particular order): 1. Check the Wireshark Protocol Statistics to get an overview of the type of traffic captured. Are all the packets meant for the mainframe (e.g. ftp, tn3270, DB2 etc). You might have a Windows server on the same VLAN generating lots of SMB traffic (or IPX or Appletalk or...) for some reason. Actually you might have to ask an OSD to capture all traffic...older OSAs used to pass through non-IP packets to the stack IIRC. 2. Any packets that Wireshark highlights in red - e.g. retransmissions, duplicate acks etc. Retransmissions almost always indicate a serious problem. 3. FTP file transfers that go faster in one direction than the other. This could indicate a duplex mismatch. Check the network switch port lights to ensure it is not flipping between 10, 100, 1000 Mbps. You mentioned turning off auto-negotiate so you've probably been there already. If nothing looks out of the ordinary and you are seeing 100+ MB/sec then I'd assume that you are maxing out your OSA. You may be able to get your network guys to prioritize FTP traffic (for example) so that your TN3270 traffic gets routed first. FWIW, in my infrequent looks at RMF reports, OSA utilizations never seem to go much higher that 5% but that could just be typical of the networks I've been involved with. Cheers, Andrew -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
On Wed, Apr 20, 2011 at 2:44 AM, Andrew Armstrong androidarmstr...@gmail.com wrote: deleted FWIW, in my infrequent looks at RMF reports, OSA utilizations never seem to go much higher that 5% but that could just be typical of the networks I've been involved with. Cheers, Andrew At 1700, our TSM on MVS drives our network card to 20% for a few hours. -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
Scott Using Jumbo Frames usually increases throughput by increasing link utilization. I must be missing something here. If by improving the efficiency as defined in http://en.wikipedia.org/wiki/Ethernet_frame you get more throughput, why is that a bad thing? It might even solve the *problem* by addressing the *issue* of efficiency. It can always save an IIRC if you turn to the manual: Open Systems Adapter-Express Customer's Guide and Reference quote The OSA-Express Gigabit Ethernet feature: - ... - Provides 1000 Mbps/full duplex operation via point-to-point link - ... /quote Chris Mason On Mon, 18 Apr 2011 15:12:54 -0400, Scott Rowe scott.r...@joann.com wrote: While switching to Jumbo Frames may be beneficial (assuming the current MTU is set to 1500), it is not likely to solve the issue. Using Jumbo Frames usually increases throughput by increasing link utilization. I kinda think they are already using Jumbo Frames if they are getting 100MB+/s. One place to check for this is the output from NETSTAT DEV for the OSA in question: field ActMtu. As far as speed/duplex settings go, they are definitively set at 1Gb, or they would not be getting throughput numbers that high, and IIRC, Gigabit is ALWAYS full duplex. On Mon, Apr 18, 2011 at 1:55 PM, Blaicher, Chris chris_blaic...@bmc.comwrote: I have never done ANY work with an OSA card, so my comment may be way off-track. Changing the size of the packet (if that is even possible in an OSA card), may buy you some reduction in the ratio of overhead bytes to data bytes. A friend was working on a problem with a saturated gigabit LAN and changed the packet size from the default to maximum and saw a huge gain. Christopher Y. Blaicher Senior Software Developer Austin Development Lab phone: 512.340.6154 mobile: 512.627.3803 fax: 512.340.6647 10431 Morado Circle Austin, TX 78759 -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Hal Merritt Sent: Monday, April 18, 2011 12:03 PM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Yes, but why? For example, we just recently had an issue where some piece of gear was configured as auto negotiate. After a lot of work, it was determined that the Cisco routers we were using don't do auto negotiate well and had somehow gotten into the wrong duplex state. We turned off auto and set speed and duplicity to fixed values. Made a huge difference. Huge. I'm thinking that networks bytes are far greater than payload bytes due to retries, etc. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 10:41 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? So, this is a Gigabit OSA? If so, 100MB is close enough to theoretical maximum data rate that it's pretty safe to say it's maxed out. On Mon, Apr 18, 2011 at 11:30 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Yes, we've checked that and it's okay. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:22 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
I didn't say it was a bad thing, I was actually trying to express that they were probably already using jumbo frames if they were getting that kind of throughput. Bad choice of words. On Tue, Apr 19, 2011 at 6:31 AM, Chris Mason chrisma...@belgacom.netwrote: Scott Using Jumbo Frames usually increases throughput by increasing link utilization. I must be missing something here. If by improving the efficiency as defined in http://en.wikipedia.org/wiki/Ethernet_frame you get more throughput, why is that a bad thing? It might even solve the *problem* by addressing the *issue* of efficiency. It can always save an IIRC if you turn to the manual: Open Systems Adapter-Express Customer's Guide and Reference quote The OSA-Express Gigabit Ethernet feature: - ... - Provides 1000 Mbps/full duplex operation via point-to-point link - ... /quote Chris Mason On Mon, 18 Apr 2011 15:12:54 -0400, Scott Rowe scott.r...@joann.com wrote: While switching to Jumbo Frames may be beneficial (assuming the current MTU is set to 1500), it is not likely to solve the issue. Using Jumbo Frames usually increases throughput by increasing link utilization. I kinda think they are already using Jumbo Frames if they are getting 100MB+/s. One place to check for this is the output from NETSTAT DEV for the OSA in question: field ActMtu. As far as speed/duplex settings go, they are definitively set at 1Gb, or they would not be getting throughput numbers that high, and IIRC, Gigabit is ALWAYS full duplex. On Mon, Apr 18, 2011 at 1:55 PM, Blaicher, Chris chris_blaic...@bmc.comwrote: I have never done ANY work with an OSA card, so my comment may be way off-track. Changing the size of the packet (if that is even possible in an OSA card), may buy you some reduction in the ratio of overhead bytes to data bytes. A friend was working on a problem with a saturated gigabit LAN and changed the packet size from the default to maximum and saw a huge gain. Christopher Y. Blaicher Senior Software Developer Austin Development Lab phone: 512.340.6154 mobile: 512.627.3803 fax: 512.340.6647 10431 Morado Circle Austin, TX 78759 -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Hal Merritt Sent: Monday, April 18, 2011 12:03 PM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Yes, but why? For example, we just recently had an issue where some piece of gear was configured as auto negotiate. After a lot of work, it was determined that the Cisco routers we were using don't do auto negotiate well and had somehow gotten into the wrong duplex state. We turned off auto and set speed and duplicity to fixed values. Made a huge difference. Huge. I'm thinking that networks bytes are far greater than payload bytes due to retries, etc. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 10:41 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? So, this is a Gigabit OSA? If so, 100MB is close enough to theoretical maximum data rate that it's pretty safe to say it's maxed out. On Mon, Apr 18, 2011 at 11:30 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Yes, we've checked that and it's okay. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:22 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html CONFIDENTIALITY/EMAIL NOTICE: The material in this transmission contains confidential and privileged information intended only for the addressee. If you are not the intended recipient, please be advised that you have received this material in error and that any forwarding, copying, printing, distribution, use or disclosure of the material is strictly prohibited. If you have received this material in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the material. Emails are not secure and can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by email. Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists
Re: When is an OSA card too busy?
Network traffic is not a good metric for 'throughput' in my opinion. 'Throughput' might best be expressed in the time needed to move a data byte end to end. A 'network' byte could be data, overhead, or the silence between packets. And the time to move a data byte end to end doubles for each hop in the path. As some have noted, jumbo frames can drastically increase throughput, lower line utilization, or both. Add compression to jumbo frames, and one can see 'throughput' numbers climb well above the advertised link capacity. Add encryption implemented such that it defeats the compression and one can see a dramatic drop in 'throughput' while seeing the same or increased network bytes. So, the OP may actually be looking at an otherwise clean path that is overloaded. Or, there may be something hurting throughput. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Tuesday, April 19, 2011 6:01 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? I didn't say it was a bad thing, I was actually trying to express that they were probably already using jumbo frames if they were getting that kind of throughput. Bad choice of words. On Tue, Apr 19, 2011 at 6:31 AM, Chris Mason chrisma...@belgacom.netwrote: Scott Using Jumbo Frames usually increases throughput by increasing link utilization. I must be missing something here. If by improving the efficiency as defined in http://en.wikipedia.org/wiki/Ethernet_frame you get more throughput, why is that a bad thing? It might even solve the *problem* by addressing the *issue* of efficiency. It can always save an IIRC if you turn to the manual: Open Systems Adapter-Express Customer's Guide and Reference quote The OSA-Express Gigabit Ethernet feature: - ... - Provides 1000 Mbps/full duplex operation via point-to-point link - ... /quote Chris Mason On Mon, 18 Apr 2011 15:12:54 -0400, Scott Rowe scott.r...@joann.com wrote: While switching to Jumbo Frames may be beneficial (assuming the current MTU is set to 1500), it is not likely to solve the issue. Using Jumbo Frames usually increases throughput by increasing link utilization. I kinda think they are already using Jumbo Frames if they are getting 100MB+/s. One place to check for this is the output from NETSTAT DEV for the OSA in question: field ActMtu. As far as speed/duplex settings go, they are definitively set at 1Gb, or they would not be getting throughput numbers that high, and IIRC, Gigabit is ALWAYS full duplex. On Mon, Apr 18, 2011 at 1:55 PM, Blaicher, Chris chris_blaic...@bmc.comwrote: I have never done ANY work with an OSA card, so my comment may be way off-track. Changing the size of the packet (if that is even possible in an OSA card), may buy you some reduction in the ratio of overhead bytes to data bytes. A friend was working on a problem with a saturated gigabit LAN and changed the packet size from the default to maximum and saw a huge gain. Christopher Y. Blaicher Senior Software Developer Austin Development Lab phone: 512.340.6154 mobile: 512.627.3803 fax: 512.340.6647 10431 Morado Circle Austin, TX 78759 -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Hal Merritt Sent: Monday, April 18, 2011 12:03 PM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Yes, but why? For example, we just recently had an issue where some piece of gear was configured as auto negotiate. After a lot of work, it was determined that the Cisco routers we were using don't do auto negotiate well and had somehow gotten into the wrong duplex state. We turned off auto and set speed and duplicity to fixed values. Made a huge difference. Huge. I'm thinking that networks bytes are far greater than payload bytes due to retries, etc. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 10:41 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? So, this is a Gigabit OSA? If so, 100MB is close enough to theoretical maximum data rate that it's pretty safe to say it's maxed out. On Mon, Apr 18, 2011 at 11:30 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Yes, we've checked that and it's okay. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:22 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. NOTICE: This electronic mail message and any files
When is an OSA card too busy?
This is a stupid question but we need to analyze the use on one of our OSA CHPIDs. Anyone who actually know anything about it is out of the office so it has fallen to me to look into it. I can tell it's not as simple as just Bus busy or Channel busy, or Read bytes and write bytes but I'm looking for a resource that can give me an idea of what combination of factors can lead you to think that an OSA may be overloaded. Any help is appreciated! Jim Horne NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
I'd open a PMR and get instructions for a trace. Do the trace and send to IBM for analysis. Poor performance could be any number of things. The 'overload' might be a DOS, excessive retries, or a configuration issue. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Horne, Jim - James S Sent: Monday, April 18, 2011 9:39 AM To: IBM-MAIN@bama.ua.edu Subject: When is an OSA card too busy? This is a stupid question but we need to analyze the use on one of our OSA CHPIDs. Anyone who actually know anything about it is out of the office so it has fallen to me to look into it. I can tell it's not as simple as just Bus busy or Channel busy, or Read bytes and write bytes but I'm looking for a resource that can give me an idea of what combination of factors can lead you to think that an OSA may be overloaded. Any help is appreciated! Jim Horne NOTICE: This electronic mail message and any files transmitted with it are intended exclusively for the individual or entity to which it is addressed. The message, together with any attachment, may contain confidential and/or privileged information. Any unauthorized review, use, printing, saving, copying, disclosure or distribution is strictly prohibited. If you have received this message in error, please immediately advise the sender by reply email and delete all copies. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
Thanks, Hal. We have opened a ticket with IBM. I'm using IBM-Main to see if I can get more/better information faster this way. Jim Horne Hal Merritt wrote: I'd open a PMR and get instructions for a trace. Do the trace and send to IBM for analysis. Poor performance could be any number of things. The 'overload' might be a DOS, excessive retries, or a configuration issue. NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
Jim The OSA specialists can more reliably be found on the IBMTCP-L list: For IBMTCP-L subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO IBMTCP-L I presume you've looked through the manual - just the one - covering the OSA (I assume you are not talking about the ICC or you would have said so - but maybe that's incorrect), namely: Open Systems Adapter-Express Customer's Guide and Reference, SA22-7935- 11 http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/IOA2Z180 and read the Chapter 10, Problem Determination Aids section Performance Data. One factor which only you, the user, knows is whether the traffic can be characterised as interactive or batch. If batch, any percentage usage up to 100 is fine. In other words, 100% is very probably too busy. However, it was always a topic for budding networking specialists in the days when time in classes could actually be devoted to the background theory of a topic and people actually found time to perform elaborate simulation exercises, that queuing theory was covered. A message that is derived from that study even if the details and the rest has atrophied in the memory is that 100% is disastrously too busy and that you need to keep some slack in the resources for which there can be queuing in order to retain acceptable response times. Wet fingers indicate percentages such as 70-80 although my judgement may be skewed towards efficient SNA and we all risk languishing at the bottom of a cliff with inefficient IP-based protocols these gadarene days. Chris Mason On Mon, 18 Apr 2011 10:39:24 -0400, Horne, Jim - James S jim.s.ho...@lowes.com wrote: This is a stupid question but we need to analyze the use on one of our OSA CHPIDs. Anyone who actually know anything about it is out of the office so it has fallen to me to look into it. I can tell it's not as simple as just Bus busy or Channel busy, or Read bytes and write bytes but I'm looking for a resource that can give me an idea of what combination of factors can lead you to think that an OSA may be overloaded. Any help is appreciated! Jim Horne -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
What is RMF telling you, and what type of OSA is it? On Mon, Apr 18, 2011 at 11:09 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Thanks, Hal. We have opened a ticket with IBM. I'm using IBM-Main to see if I can get more/better information faster this way. Jim Horne Hal Merritt wrote: I'd open a PMR and get instructions for a trace. Do the trace and send to IBM for analysis. Poor performance could be any number of things. The 'overload' might be a DOS, excessive retries, or a configuration issue. NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html CONFIDENTIALITY/EMAIL NOTICE: The material in this transmission contains confidential and privileged information intended only for the addressee. If you are not the intended recipient, please be advised that you have received this material in error and that any forwarding, copying, printing, distribution, use or disclosure of the material is strictly prohibited. If you have received this material in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the material. Emails are not secure and can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by email. Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. On Mon, Apr 18, 2011 at 11:09 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Thanks, Hal. We have opened a ticket with IBM. I'm using IBM-Main to see if I can get more/better information faster this way. Jim Horne Hal Merritt wrote: I'd open a PMR and get instructions for a trace. Do the trace and send to IBM for analysis. Poor performance could be any number of things. The 'overload' might be a DOS, excessive retries, or a configuration issue. NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html CONFIDENTIALITY/EMAIL NOTICE: The material in this transmission contains confidential and privileged information intended only for the addressee. If you are not the intended recipient, please be advised that you have received this material in error and that any forwarding, copying, printing, distribution, use or disclosure of the material is strictly prohibited. If you have received this material in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the material. Emails are not secure and can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by email. Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
It's defined as an OSD and in the period we care about, we see Bus busy and channel busy better than 5%, read bytes/sec better than 100 Megabytes/sec and write bytes at a little over 2 Megabytes/sec. Normally the read rate is about 100X less and the write rate is about 10X less. We know we're in trouble in this interval; we're trying to determine guidelines for predicting trouble. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:18 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? What is RMF telling you, and what type of OSA is it? NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
Yes, we've checked that and it's okay. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:22 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
So, this is a Gigabit OSA? If so, 100MB is close enough to theoretical maximum data rate that it's pretty safe to say it's maxed out. On Mon, Apr 18, 2011 at 11:30 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Yes, we've checked that and it's okay. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:22 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html CONFIDENTIALITY/EMAIL NOTICE: The material in this transmission contains confidential and privileged information intended only for the addressee. If you are not the intended recipient, please be advised that you have received this material in error and that any forwarding, copying, printing, distribution, use or disclosure of the material is strictly prohibited. If you have received this material in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the material. Emails are not secure and can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by email. Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
Yes, but why? For example, we just recently had an issue where some piece of gear was configured as auto negotiate. After a lot of work, it was determined that the Cisco routers we were using don't do auto negotiate well and had somehow gotten into the wrong duplex state. We turned off auto and set speed and duplicity to fixed values. Made a huge difference. Huge. I'm thinking that networks bytes are far greater than payload bytes due to retries, etc. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 10:41 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? So, this is a Gigabit OSA? If so, 100MB is close enough to theoretical maximum data rate that it's pretty safe to say it's maxed out. On Mon, Apr 18, 2011 at 11:30 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Yes, we've checked that and it's okay. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:22 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html CONFIDENTIALITY/EMAIL NOTICE: The material in this transmission contains confidential and privileged information intended only for the addressee. If you are not the intended recipient, please be advised that you have received this material in error and that any forwarding, copying, printing, distribution, use or disclosure of the material is strictly prohibited. If you have received this material in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the material. Emails are not secure and can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by email. Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html NOTICE: This electronic mail message and any files transmitted with it are intended exclusively for the individual or entity to which it is addressed. The message, together with any attachment, may contain confidential and/or privileged information. Any unauthorized review, use, printing, saving, copying, disclosure or distribution is strictly prohibited. If you have received this message in error, please immediately advise the sender by reply email and delete all copies. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
I have never done ANY work with an OSA card, so my comment may be way off-track. Changing the size of the packet (if that is even possible in an OSA card), may buy you some reduction in the ratio of overhead bytes to data bytes. A friend was working on a problem with a saturated gigabit LAN and changed the packet size from the default to maximum and saw a huge gain. Christopher Y. Blaicher Senior Software Developer Austin Development Lab phone: 512.340.6154 mobile: 512.627.3803 fax: 512.340.6647 10431 Morado Circle Austin, TX 78759 -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Hal Merritt Sent: Monday, April 18, 2011 12:03 PM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Yes, but why? For example, we just recently had an issue where some piece of gear was configured as auto negotiate. After a lot of work, it was determined that the Cisco routers we were using don't do auto negotiate well and had somehow gotten into the wrong duplex state. We turned off auto and set speed and duplicity to fixed values. Made a huge difference. Huge. I'm thinking that networks bytes are far greater than payload bytes due to retries, etc. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 10:41 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? So, this is a Gigabit OSA? If so, 100MB is close enough to theoretical maximum data rate that it's pretty safe to say it's maxed out. On Mon, Apr 18, 2011 at 11:30 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Yes, we've checked that and it's okay. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:22 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html CONFIDENTIALITY/EMAIL NOTICE: The material in this transmission contains confidential and privileged information intended only for the addressee. If you are not the intended recipient, please be advised that you have received this material in error and that any forwarding, copying, printing, distribution, use or disclosure of the material is strictly prohibited. If you have received this material in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the material. Emails are not secure and can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by email. Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html NOTICE: This electronic mail message and any files transmitted with it are intended exclusively for the individual or entity to which it is addressed. The message, together with any attachment, may contain confidential and/or privileged information. Any unauthorized review, use, printing, saving, copying, disclosure or distribution is strictly prohibited. If you have received this message in error, please immediately advise the sender by reply email and delete all copies. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: When is an OSA card too busy?
While switching to Jumbo Frames may be beneficial (assuming the current MTU is set to 1500), it is not likely to solve the issue. Using Jumbo Frames usually increases throughput by increasing link utilization. I kinda think they are already using Jumbo Frames if they are getting 100MB+/s. One place to check for this is the output from NETSTAT DEV for the OSA in question: field ActMtu. As far as speed/duplex settings go, they are definitively set at 1Gb, or they would not be getting throughput numbers that high, and IIRC, Gigabit is ALWAYS full duplex. On Mon, Apr 18, 2011 at 1:55 PM, Blaicher, Chris chris_blaic...@bmc.comwrote: I have never done ANY work with an OSA card, so my comment may be way off-track. Changing the size of the packet (if that is even possible in an OSA card), may buy you some reduction in the ratio of overhead bytes to data bytes. A friend was working on a problem with a saturated gigabit LAN and changed the packet size from the default to maximum and saw a huge gain. Christopher Y. Blaicher Senior Software Developer Austin Development Lab phone: 512.340.6154 mobile: 512.627.3803 fax: 512.340.6647 10431 Morado Circle Austin, TX 78759 -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Hal Merritt Sent: Monday, April 18, 2011 12:03 PM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Yes, but why? For example, we just recently had an issue where some piece of gear was configured as auto negotiate. After a lot of work, it was determined that the Cisco routers we were using don't do auto negotiate well and had somehow gotten into the wrong duplex state. We turned off auto and set speed and duplicity to fixed values. Made a huge difference. Huge. I'm thinking that networks bytes are far greater than payload bytes due to retries, etc. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 10:41 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? So, this is a Gigabit OSA? If so, 100MB is close enough to theoretical maximum data rate that it's pretty safe to say it's maxed out. On Mon, Apr 18, 2011 at 11:30 AM, Horne, Jim - James S jim.s.ho...@lowes.com wrote: Yes, we've checked that and it's okay. Jim Horne -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Scott Rowe Sent: Monday, April 18, 2011 11:22 AM To: IBM-MAIN@bama.ua.edu Subject: Re: When is an OSA card too busy? Also, have you checked that the OSA is connected at the proper speed and duplex? This can be done through the HMC. NOTICE: All information in and attached to the e-mail(s) below may be proprietary, confidential, privileged and otherwise protected from improper or erroneous disclosure. If you are not the sender's intended recipient, you are not authorized to intercept, read, print, retain, copy, forward, or disseminate this message. If you have erroneously received this communication, please notify the sender immediately by phone (704-758-1000) or by e-mail and destroy all copies of this message (electronic, paper, or otherwise). Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html CONFIDENTIALITY/EMAIL NOTICE: The material in this transmission contains confidential and privileged information intended only for the addressee. If you are not the intended recipient, please be advised that you have received this material in error and that any forwarding, copying, printing, distribution, use or disclosure of the material is strictly prohibited. If you have received this material in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the material. Emails are not secure and can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by email. Thank you. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html NOTICE: This electronic mail message and any files transmitted with it are intended exclusively for the individual or entity to which it is addressed. The message, together with any attachment, may contain confidential and/or privileged information. Any unauthorized review, use, printing, saving, copying, disclosure or distribution is strictly
