On Dec 11, 2007 9:53 PM, Douglas Wagner <<a href="mailto:douglasw0@gmail.com">douglasw0@gmail.com</a>> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div><div></div><div class="Wj3C7c"><br><br><div class="gmail_quote">On Dec 11, 2007 3:37 PM, Craig Huff <<a href="mailto:huffcslists@gmail.com" target="_blank">huffcslists@gmail.com</a>> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div>On Dec 11, 2007 11:37 AM, Stephen Robertson <<a href="mailto:stephengrobertson@gmail.com" target="_blank">stephengrobertson@gmail.com</a>> wrote:<br>> I hope you will excuse what is hopefully a very simple question. I've
<br>> noticed an issue with my myth system(1 diskless frontend and 1 backend) if I<br>> am recording two dvb programs and watching one already recorded program.<br>> Mostly everything is fine however skipping/fast forwarding/rewinding is
<br>> incredibly slow though it usually does resolve itself without falling over..<br>> Backend CPU and memory usage does not seem to show anything untoward and to<br>> be honest I'm not sure how to sensibly measure any disk access parameters.
<br>> The disk for the recordings is used solely for storing recordings and is<br>> XFS.<br>><br></div>Try executing the command "iostat 4 5".<br><br>This will report I/O statistics for five samples separated by four
<br>seconds each. The first<br>report will be cumulative statistics since the system was last booted.<br> The man page will<br>explain what it tells you. It is easy to have an I/O bound system<br>that doesn't show the
<br>CPU burdened significantly, and this sounds like your problem. Do you<br>have your<br>recordings on a different disk than the O/S and mysql database?<br>Hosting them all on the<br>same disk is frequently a cause of problems.
<br><br></blockquote></div></div></div></blockquote></div>Just to follow up on my original post. I believe I have tracked down the cause of my problem and it was just one of those weird coincidences. I had inadvertanlty moved my backend machine and this had dislodged one of my TV cards so my log was filling up incredibly quickly with error messages which I only discovered when they used up the 2Gb that was free on that disk. This just happened to occur at probably the first time I have tried watching a recording while both tuners were supposed to be in use!
<br><br>I've since checked the operation (with everything plugged in correctly!!) and it can quite happily cope with FF/REW through a recording while simultaneously recording two new shows.<br><br>Thanks for your pointers.
<br><br>Stephen.<br>