Re: PAE tuning
Chuck Swiger wrote: Oh, yes, one more thought-- your specific application, i.e. a large database, is one where running in 64-bit mode is highly likely to result in improved performance compared with running the OS in 32-bit mode. If you've got a AMD64 or EM64T capable CPU, consider installing the 64-bit version of FreeBSD instead of the normal 32-bit x86 version. ---Chuck Chuck, I've heard this idea a few times in answer to my question. Is there a 64 bit Intel distro I'm missing? I saw someone suggesting I use the AMD64 version, but when I attempt to boot that from the install disk I get some debugging output and a message saying BTX halted - I suspect that means I can't follow that suggestion... Thanks again for all your help! --Paul ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: PAE tuning
Paul Lathrop wrote: Chuck Swiger wrote: Oh, yes, one more thought-- your specific application, i.e. a large database, is one where running in 64-bit mode is highly likely to result in improved performance compared with running the OS in 32-bit mode. If you've got a AMD64 or EM64T capable CPU, consider installing the 64-bit version of FreeBSD instead of the normal 32-bit x86 version. ---Chuck Chuck, I've heard this idea a few times in answer to my question. Is there a 64 bit Intel distro I'm missing? I saw someone suggesting I use the AMD64 version, but when I attempt to boot that from the install disk I get some debugging output and a message saying BTX halted - I suspect that means I can't follow that suggestion... Thanks again for all your help! I figured it out - this is an older Xeon processor apparently - 32 bit. Sorry for the cluelessness - I'm a bit behind the times when it comes to hardware. Regards, Paul ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: PAE tuning
On 2006/10/06 9:08, Paul Lathrop seems to have typed: Is there a 64 bit Intel distro I'm missing? I saw someone suggesting I use the AMD64 version, but when I attempt to boot that from the install disk I get some debugging output and a message saying BTX halted - I suspect that means I can't follow that suggestion... Theoretically, amd64 should work on a Xeon (depending on which Xeon you are using, more system details would be required to say for sure) See: http://www.freebsd.org/releases/6.1R/hardware-amd64.html *** QUOTE *** Since mid-2003 FreeBSD/amd64 has supported the AMD64 (“Hammer”) and Intel EM64T architecture, and is now one of the Tier-1 platforms (fully supported architecture), which are expected to be Production Quality with respects to all aspects of the FreeBSD operating system, including installation and development environments. Note that there are two names for this architecture, AMD64 (AMD) and Intel EM64T (Extended Memory 64-bit Technology). 64-bit mode of the two architectures are almost compatible with each other, and FreeBSD/amd64 should support them both. As of this writing, the following processors are supported: * AMD Athlon64 (“Clawhammer”). * AMD Opteron (“Sledgehammer”). * Intel 64-bit Xeon (“Nacona”). This processor is fabricated on 90nm process technology, and operates with 2.80 to 3.60 GHz (FSB 800MHz) and Intel E7520/E7525/E7320 chipsets. * Intel Pentium 4 Processor supporting Intel EM64T (“Prescott”). This is fabricated on 90nm process technology, uses FC-LGA775 package, and operates with 3.20F/3.40F/3.60F GHz and Intel 925X Express chipsets. The corresponding S-Spec numbers are SL7L9, SL7L8, SL7LA, SL7NZ, SL7PZ, and SL7PX. Note that processors marked as 5xx numbers do not support EM64T. Intel EM64T is an extended version of IA-32 (x86) and different from Intel IA-64 (Itanium) architecture, which FreeBSD/ia64 supports. Some Intel's old documentation refers to Intel EM64T as “64-bit extension technology” or “IA-32e”. *** END QUOTE *** There is a lot of information about the BTX halted error message in the archives if you believe your system should be supported: http://www.freebsd.org/cgi/search.cgi?words=%22BTX+halted%22max=25sort=scoreindex=recentsource=freebsd-questions ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
PAE tuning
Hi all, I just built a new Intel Xeon FreeBSD 6.1 server with 14Gb of RAM. I started digging into PAE so that we could actually make use of the high memory in this box, and I've run into a rather vexing issue. The handbook says: Some system tunables determine memory resource usage by the amount of available physical memory. Such tunables can unnecessarily over-allocate due to the large memory nature of a PAE system. One such example is the kern.maxvnodes sysctl, which controls the maximum number of vnodes allowed in the kernel. It is advised to adjust this and other such tunables to a reasonable value. That's really good to know. Unfortunately, nobody seems to have written down WHICH tunables need to be adjusted besides the one mentioned above, nor is there any information on what reasonable value means! Can anyone point me at a resource for more information on this? Regards, Paul Lathrop signature.asc Description: OpenPGP digital signature
Re: PAE tuning
On Oct 5, 2006, at 11:29 AM, Paul Lathrop wrote: That's really good to know. Unfortunately, nobody seems to have written down WHICH tunables need to be adjusted besides the one mentioned above, nor is there any information on what reasonable value means! Can anyone point me at a resource for more information on this? You're supposed to tune the appropriate values considering the workload the machine is going to handle. man tuning has some additional information, but without describing what kind of tasks you plan to do with this machine with 14GB of RAM, nobody is going to be able to provide you with really specific advice... -- -Chuck ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: PAE tuning
Chuck Swiger wrote: On Oct 5, 2006, at 11:29 AM, Paul Lathrop wrote: That's really good to know. Unfortunately, nobody seems to have written down WHICH tunables need to be adjusted besides the one mentioned above, nor is there any information on what reasonable value means! Can anyone point me at a resource for more information on this? You're supposed to tune the appropriate values considering the workload the machine is going to handle. man tuning has some additional information, but without describing what kind of tasks you plan to do with this machine with 14GB of RAM, nobody is going to be able to provide you with really specific advice... Good point. :-) I intend to deploy this system as a database server running Postgresql 8.1. The database is huge (30-40Gb) and can easily grow (it has gone as high as 100Gb). I expect as many as 1000 concurrent database connections now, and a potential need for scaling this up later. I'm aware of the SystemV memory tuning issues related to running Postgres on FreeBSD and I'll address those as soon as I can get the system to see the RAM. I tried just installing the stock PAE kernel, but the system still doesn't even acknowledge the RAM above 4Gb. Is this because I have not yet performed the tuning? Thanks for your help! --Paul signature.asc Description: OpenPGP digital signature
Re: PAE tuning
On Oct 5, 2006, at 12:13 PM, Paul Lathrop wrote: You're supposed to tune the appropriate values considering the workload the machine is going to handle. man tuning has some additional information, but without describing what kind of tasks you plan to do with this machine with 14GB of RAM, nobody is going to be able to provide you with really specific advice... Good point. :-) I intend to deploy this system as a database server running Postgresql 8.1. The database is huge (30-40Gb) and can easily grow (it has gone as high as 100Gb). I expect as many as 1000 concurrent database connections now, and a potential need for scaling this up later. You should tune the network stack settings towards LAN use (shorter timeouts, larger send receive buffers); you should probably tune down the # of vnodes, adjust SysV shared memory as Postgres recommends: I'm aware of the SystemV memory tuning issues related to running Postgres on FreeBSD and I'll address those as soon as I can get the system to see the RAM. I tried just installing the stock PAE kernel, but the system still doesn't even acknowledge the RAM above 4Gb. Is this because I have not yet performed the tuning? Update your BIOS and then check the settings; there may be an option explicitly for PAE, or you might find that tweaking something like PCI memory reservation, 4GB memory hole, or MTRR mapping between the options will help make the extra memory appear. -- -Chuck ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: PAE tuning
On Oct 5, 2006, at 12:13 PM, Paul Lathrop wrote: I intend to deploy this system as a database server running Postgresql 8.1. The database is huge (30-40Gb) and can easily grow (it has gone as high as 100Gb). Oh, yes, one more thought-- your specific application, i.e. a large database, is one where running in 64-bit mode is highly likely to result in improved performance compared with running the OS in 32-bit mode. If you've got a AMD64 or EM64T capable CPU, consider installing the 64-bit version of FreeBSD instead of the normal 32-bit x86 version. -- -Chuck ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: PAE tuning
Have you thought in using 6.1/amd64 instead of 6.1/i386 + PAE ? Your Xeon processor is supported under the amd64 port, using EM64T for addressing more than 4GB. I had some stability troubles in the past running mysql server with PAE enabled, for a 6GB RAM server. Regards On Thu, 5 Oct 2006, Paul Lathrop wrote: Chuck Swiger wrote: On Oct 5, 2006, at 11:29 AM, Paul Lathrop wrote: That's really good to know. Unfortunately, nobody seems to have written down WHICH tunables need to be adjusted besides the one mentioned above, nor is there any information on what reasonable value means! Can anyone point me at a resource for more information on this? You're supposed to tune the appropriate values considering the workload the machine is going to handle. man tuning has some additional information, but without describing what kind of tasks you plan to do with this machine with 14GB of RAM, nobody is going to be able to provide you with really specific advice... Good point. :-) I intend to deploy this system as a database server running Postgresql 8.1. The database is huge (30-40Gb) and can easily grow (it has gone as high as 100Gb). I expect as many as 1000 concurrent database connections now, and a potential need for scaling this up later. I'm aware of the SystemV memory tuning issues related to running Postgres on FreeBSD and I'll address those as soon as I can get the system to see the RAM. I tried just installing the stock PAE kernel, but the system still doesn't even acknowledge the RAM above 4Gb. Is this because I have not yet performed the tuning? Thanks for your help! --Paul ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: PAE tuning
Chuck Swiger wrote: On Oct 5, 2006, at 12:13 PM, Paul Lathrop wrote: You should tune the network stack settings towards LAN use (shorter timeouts, larger send receive buffers); you should probably tune down the # of vnodes, adjust SysV shared memory as Postgres recommends: Update your BIOS and then check the settings; there may be an option explicitly for PAE, or you might find that tweaking something like PCI memory reservation, 4GB memory hole, or MTRR mapping between the options will help make the extra memory appear. Chuck, Many thanks for your advice. Is this information gleaned from experience or is there an information resource out there that I might utilize in the future when I deploy other applications? Regards, Paul Lathrop signature.asc Description: OpenPGP digital signature
Re: PAE tuning
On 2006/10/05 10:29, Paul Lathrop seems to have typed: I just built a new Intel Xeon FreeBSD 6.1 server with 14Gb of RAM. I started digging into PAE so that we could actually make use of the high memory in this box The other thing you might consider is that if that Xeon system is 64bit (and if its a new system, its likely the Woodcrest Xeon which are 64bit), you could use the AMD64 version and make use of the memory in that way. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: PAE tuning
On Oct 5, 2006, at 12:34 PM, Paul Lathrop wrote: Many thanks for your advice. Well, you are most welcome. Is this information gleaned from experience or is there an information resource out there that I might utilize in the future when I deploy other applications? Yes, this information is gleaned from experience (why, yes, I have installed 12GB of RAM into an 8-CPU Sun E4500 myself :-), but also, yes, there are some good resources available. O'Reilly publishes a book called System Performance Tuning, ISBN: 059600284X which is a decent read, although it is somewhat oriented towards classic Solaris, AIX, other SysV-derived Unices more than BSD or Linux. Some of the online websites like Anandtech Tom's Hardware used to have some excellent discussions of BIOS settings, memory configuration and timing, etc, although nowadays those sites are putting so many ads and intrusive Javascript/Flash-based annoyances in the way that their useful content is much harder to find or read than it used to be. (I've stopped going to both sites a few years ago, when the proportion of content to ads dropped below my acceptable signal-to-noise ratio...) -- -Chuck ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
