Re: [Asterisk-Users] TDM400P and SCSI/SATA = * noise problems???
Damian Funnell wrote: When I asked them for further information on how to improve this they replied: ** Extract begins ** SCSI RAID can cause the problem. If disabling hyper threading does not resolve your problem my next suggest would be to revert to a PATA IDE hard drive solution configured to UDMA level 2 using hdparm. SCSI or SATA causes problems on some systems from what I have seen. The problem increases when using a SCSI or SATA RAID. ** Extract ends ** I really hope that they are wrong, as I don't feel like throwing away my nice expensive Ultra320 SCSI RAID controller and hot plug drives and replacing them with some crusty old IDE config. Needless to say I'm not going to go and shell out on IDE controller drives until I'm a little more certain that this is actually a problem and have asked them for more information. I've gotten some iffy advice from Digium tech support before. There is not a specific issue with RAID that I know of. However, it is common for some kernel modules to lock interrupts for very long amounts of time. This will cause problems. Graphics is well known for this, as is some RAID drivers. ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] TDM400P and SCSI/SATA = * noise problems???
[EMAIL PROTECTED] wrote on 04/19/2005 01:32:57 AM: ** Extract begins ** SCSI RAID can cause the problem. If disabling hyper threading does not resolve your problem my next suggest would be to revert to a PATA IDE hard drive solution configured to UDMA level 2 using hdparm. SCSI or SATA causes problems on some systems from what I have seen. The problem increases when using a SCSI or SATA RAID. ** Extract ends ** I really hope that they are wrong, as I don't feel like throwing away my nice expensive Ultra320 SCSI RAID controller and hot plug drives and replacing them with some crusty old IDE config. Needless to say I'm not going to go and shell out on IDE controller drives until I'm a little more certain that this is actually a problem and have asked them for more information. Does anyone else find it odd that the TDM could possibly have a problem sharing a box (but not an IRQ) with a SCSI controller? Yes. It has to do with latency and bus contention. I've run a TDM board in an IBM Netfinity 5600 server with an IBM ServeRAID 3L controller (SCSI-U2W). The big difference, though, is that the RAID controller was on its own PCI bus, and the TDM card was on its own PCI bus. With both controllers on the bus, you can have latency issues. For example, if the RAID controller sets up a DMA of a big chunk of disk, it owns the bus for that transfer. If an Ethernet packet is delayed by 50us during that time, nobody cares. But if the TDM card is delayed, it most certainly cares: especially as its generating 1000 interrupts a second! That's the problem with the TDM cards. They do *nothing* on the CPU side. The CPU has to do *everything*, and it has to do it *immediately*. When you are using plain-jane IDE, you can tweak the kernel to put the IDE stuff at a low priority. But when you've got a fancy RAID controller, it tends to think it's the most important thing in the system. And as a rule, hard drive I/O usually *is* the most important I/O going on in a system. However, in this case, the TDM card trumps that. And Digium doesn't know how to tweak every last RAID driver in existence for low-priority operation--or even if it's possible. Hence, the recommendation for IDE. Combined with the fact that they have also recommended that we turn off hyper threading (also causes problems with TDM, apparently), I'm wondering if these cards shouldn't come with a warning not to use anything with half decent performance in your * server! Yet they require PCI 2.2, which eliminates most Pentium III's and lower! :) I'm still in the midst of testing the TDM cards. So far, so good, in an EPIA-based solution and in the 5600. But I've been through at least half a dozen different systems before I've found these... Tim Massey ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] TDM400P and SCSI/SATA = * noise problems???
SATA works ok for me, but its not like I am running a DB server on that box, just a TTS engine and some audio files. It would be nice though. I had some trouble getting my TE405P cards to talk, and got some helpful advise from the folks at Digium excerpt: You may need to disable unnecessary hardware on your machine such as sound controllers, USB controllers, extra ethernet controllers, firewire, parallel ports, and/or serial ports. and If you are running an IDE hard drive please verify that you are using DMA mode with a UDMA setting of no lower than 2 or higher than 3. UDMA mode 2 is ATA33 - We would suggest using an IDE harddrive rather than SCSI or SATA in order to configure your hard drive to UDMA2. Configuring a SCSI or SATA hard drive to UDMA2 is not possible. Well there goes disk performance :-P and Please ensure that you are not running X-Windows, frame-buffer, or serial console, as these will cause problems with our hardware. oh, and If you are still having IRQ misses with our hardware you could try booting your kernel with acpi=off and/or noapic to disable ACPI power management andAPIC. These has been known to cause interrupt sharing problems as well. The good news is that it will probably work if you do all that stuff ;-) - Ben___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] TDM400P and SCSI/SATA = * noise problems???
Hi Tim, Thanks for your post, it's most insightful. It certainly puts a pretty large dent in my confidence in the TDM for commercial use - imagine if there was more than one TDM in a system (especially with a RAID adapter). Running a PABX without hardware RAID 0 is not an option for us, as we don't want disk failure to result in the PABX dying, so I guess we are going to have to research ways of retarding it somehow. Cheers, D. FFF Managed Technology Ltd 60 Cook St P.O. 6368 Wellesley St Auckland t +64 9 356 2911 f +64 9 358 9070 m +64 21 415 297 w www.fff.co.nz [EMAIL PROTECTED] wrote: Yes. It has to do with latency and bus contention. I've run a TDM board in an IBM Netfinity 5600 server with an IBM ServeRAID 3L controller (SCSI-U2W). The big difference, though, is that the RAID controller was on its own PCI bus, and the TDM card was on its own PCI bus. With both controllers on the bus, you can have latency issues. For example, if the RAID controller sets up a DMA of a big chunk of disk, it owns the bus for that transfer. If an Ethernet packet is delayed by 50us during that time, nobody cares. But if the TDM card is delayed, it most certainly cares: especially as its generating 1000 interrupts a second! That's the problem with the TDM cards. They do *nothing* on the CPU side. The CPU has to do *everything*, and it has to do it *immediately*. When you are using plain-jane IDE, you can tweak the kernel to put the IDE stuff at a low priority. But when you've got a fancy RAID controller, it tends to think it's the most important thing in the system. And as a rule, hard drive I/O usually *is* the most important I/O going on in a system. However, in this case, the TDM card trumps that. And Digium doesn't know how to tweak every last RAID driver in existence for low-priority operation--or even if it's possible. Hence, the recommendation for IDE. Yet they require PCI 2.2, which eliminates most Pentium III's and lower! :) I'm still in the midst of testing the TDM cards. So far, so good, in an EPIA-based solution and in the 5600. But I've been through at least half a dozen different systems before I've found these... Tim Massey ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [Asterisk-Users] TDM400P and SCSI/SATA = * noise problems???
On Apr 19, 2005, at 12:30 PM, Damian Funnell wrote: Thanks for your post, it's most insightful. It certainly puts a pretty large dent in my confidence in the TDM for commercial use - imagine if there was more than one TDM in a system (especially with a RAID adapter). Running a PABX without hardware RAID 0 is not an option for us, as we don't want disk failure to result in the PABX dying, so I guess we are going to have to research ways of retarding it somehow. I assume that this is a typo--RAID 0 makes disk failure *more* likely, not less likely. RAID 1 (or higher) is needed to provide redundancy. Scott ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
RE: [Asterisk-Users] TDM400P and SCSI/SATA = * noise problems???
We're running asterisk on a pair of 1GB 12mb/s flash cards running on separate IDE channels. We've setup software RAID1 to protect ourselves from failures if any of the flash cards die. VoiceMail is stored on a small IDE that is dedicated just for this. It appears to work quite well. Although we don't have TDM's on our system. -Original Message- From: [EMAIL PROTECTED] [mailto:asterisk-users- [EMAIL PROTECTED] On Behalf Of Damian Funnell Sent: Wednesday, 20 April 2005 05:30 To: Asterisk Users Mailing List - Non-Commercial Discussion Subject: Re: [Asterisk-Users] TDM400P and SCSI/SATA = * noise problems??? Hi Tim, Thanks for your post, it's most insightful. It certainly puts a pretty large dent in my confidence in the TDM for commercial use - imagine if there was more than one TDM in a system (especially with a RAID adapter). Running a PABX without hardware RAID 0 is not an option for us, as we don't want disk failure to result in the PABX dying, so I guess we are going to have to research ways of retarding it somehow. Cheers, D. FFF Managed Technology Ltd 60 Cook St P.O. 6368 Wellesley St Auckland t +64 9 356 2911 f +64 9 358 9070 m +64 21 415 297 w www.fff.co.nz [EMAIL PROTECTED] wrote: Yes. It has to do with latency and bus contention. I've run a TDM board in an IBM Netfinity 5600 server with an IBM ServeRAID 3L controller (SCSI-U2W). The big difference, though, is that the RAID controller was on its own PCI bus, and the TDM card was on its own PCI bus. With both controllers on the bus, you can have latency issues. For example, if the RAID controller sets up a DMA of a big chunk of disk, it owns the bus for that transfer. If an Ethernet packet is delayed by 50us during that time, nobody cares. But if the TDM card is delayed, it most certainly cares: especially as its generating 1000 interrupts a second! That's the problem with the TDM cards. They do *nothing* on the CPU side. The CPU has to do *everything*, and it has to do it *immediately*. When you are using plain-jane IDE, you can tweak the kernel to put the IDE stuff at a low priority. But when you've got a fancy RAID controller, it tends to think it's the most important thing in the system. And as a rule, hard drive I/O usually *is* the most important I/O going on in a system. However, in this case, the TDM card trumps that. And Digium doesn't know how to tweak every last RAID driver in existence for low-priority operation--or even if it's possible. Hence, the recommendation for IDE. Yet they require PCI 2.2, which eliminates most Pentium III's and lower! :) I'm still in the midst of testing the TDM cards. So far, so good, in an EPIA-based solution and in the 5600. But I've been through at least half a dozen different systems before I've found these... Tim Massey ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users This message (and any associated files) is intended only for the use of the individual or entity to which it is addressed and may contain information that is confidential, subject to copyright or constitutes a trade secret. If you are not the intended recipient you are hereby notified that any dissemination, copying or distribution of this message, or files associated with this message, is strictly prohibited. If you have received this message in error, please notify us immediately by replying to the message and deleting it from your computer. Messages sent to and from us may be monitored... Internet communications cannot be guaranteed to be secured or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. Therefore, we do not accept responsibility for any errors or omissions that are present in this message, or any attachment, that have arisen as a result of e-mail transmission. If verification is required, please request a hard-copy version. Any views or opinions presented are solely those of the author and do not necessarily represent those of the company. ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
[Asterisk-Users] TDM400P and SCSI/SATA = * noise problems???
Hi everyone, For anyone who was following the earlier thread about noise problems on *, here's a little gem from Digium support. In a nutshell Digium told us that they thought that low accuracy results from zttest were the cause of noise problems that we have been experiencing. We re-configured the box to give the TDM400P its own IRQ, but found that the zttest results were still lower than what Digium recommended they should be. When I asked them for further information on how to improve this they replied: ** Extract begins ** SCSI RAID can cause the problem. If disabling hyper threading does not resolve your problem my next suggest would be to revert to a PATA IDE hard drive solution configured to UDMA level 2 using hdparm. SCSI or SATA causes problems on some systems from what I have seen. The problem increases when using a SCSI or SATA RAID. ** Extract ends ** I really hope that they are wrong, as I don't feel like throwing away my nice expensive Ultra320 SCSI RAID controller and hot plug drives and replacing them with some crusty old IDE config. Needless to say I'm not going to go and shell out on IDE controller drives until I'm a little more certain that this is actually a problem and have asked them for more information. Does anyone else find it odd that the TDM could possibly have a problem sharing a box (but not an IRQ) with a SCSI controller? Combined with the fact that they have also recommended that we turn off hyper threading (also causes problems with TDM, apparently), I'm wondering if these cards shouldn't come with a warning not to use anything with half decent performance in your * server! ___ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
