Re: [gentoo-user] 2GB of RAM
* Ralph Slooten [EMAIL PROTECTED] [2006-06-21 00:15]: I upgraded yesterday to 2.6.17 and also noticed that there was no split option. Not thinking much of it I installed the kernel which works fine, except now /proc/kcore reports 897M, and `free` something to that effect too. So I take it I'm only using just less than 1/2 my RAM now, correct? Right. With 2GB of RAM, Do I now have to enable the embedded option (which gives me a lot more options, most likely all of which I don't need), and then select the 2/2 split, or ? Actually, I side with the kernel developers on this; the fact that they're hiding the VMSPLIT options is basically a subtle hint that they don't want people using them who don't *really* know what they're doing. I strongly suggest using CONFIG_HIGHMEM, and sticking with the default 3/1 split. (I mean, it's *slightly* slower, but on the other hand what caused them to do this was random breaking of java that took a long time to diagnose.) That said... I noticed too that if I select the embedded option, but unselect all new options that come with it I still get the memory split options. Is this the right way to go? NO. As in, all of those options (with the exception of CONFIG_KALLSYMS_EXTRA_PASS) default to yes, and all of those defaults are very important. If you disable them, you will, for example, break most of the kernel's logging (printk), lose the ability to get core dumps, and lose futexes (which will break a lot of modern threading). Basically, saying no to any option option on that page (with the exception of the KALLSYMS stuff) *WILL* break your system. So, make sure that everything, except CONFIG_KALLSYMS_EXTRA_PASS, on that page is enabled. (that might be what you meant in the first place, of course, but it's worth making sure...) All you need to be able to select the VMSPLIT options is CONFIG_EMBEDDED (that is, saying yes to the Configure standard kernel features (for small systems) item) which doesn't actually have any impact on the code. Hope this helps. -- David Klempner pgpOKI6BImABq.pgp Description: PGP signature
Re: [gentoo-user] 2GB of RAM
* Vladimir G. Ivanovic [EMAIL PROTECTED] [2006-06-20 16:51]: I figured it out. The VMSPLIT options are *not* available on 64-bit systems. (Phew. It's neither encroaching madness nor Alzheimer's.) Yeah... I suppose I wasn't paying close enough attention to what you were saying. :-) The VMSPLIT options are about how the kernel uses the 32 bit address space (specifically, what fraction of the address space of each process it reserves for its own use). A large portion of what a 64 bit system gets you is more than 32 bits worth of address space, so I'm fairly sure the entire issue is moot. :-) (On the other hand, I have still yet to look really closely at the gory details of how AMD64 works, and how linux uses it. I had a decent idea, way back when the only implementations available were simulators, but that was a while ago and I've forgotten a lot of it. As such, I might be wrong.) -- David Klempner pgpehjRSoldKu.pgp Description: PGP signature
Re: [gentoo-user] 2GB of RAM
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi David, David Klempner wrote: Actually, I side with the kernel developers on this; the fact that they're hiding the VMSPLIT options is basically a subtle hint that they don't want people using them who don't *really* know what they're doing. Like me .. hence all the questions ;-) I just want to be able to use my full RAM, as having 2GB and using 1GB is just uncool ;-) I strongly suggest using CONFIG_HIGHMEM, and sticking with the default 3/1 split. (I mean, it's *slightly* slower, but on the other hand what caused them to do this was random breaking of java that took a long time to diagnose.) That said... OK. I definitely will keep this in mind. I noticed too that if I select the embedded option, but unselect all new options that come with it I still get the memory split options. Is this the right way to go? NO. As in, all of those options (with the exception of CONFIG_KALLSYMS_EXTRA_PASS) default to yes, and all of those defaults are very important. If you disable them, you will, for example, break most of the kernel's logging (printk), lose the ability to get core dumps, and lose futexes (which will break a lot of modern threading). Basically, saying no to any option option on that page (with the exception of the KALLSYMS stuff) *WILL* break your system. So, make sure that everything, except CONFIG_KALLSYMS_EXTRA_PASS, on that page is enabled. (that might be what you meant in the first place, of course, but it's worth making sure...) All you need to be able to select the VMSPLIT options is CONFIG_EMBEDDED (that is, saying yes to the Configure standard kernel features (for small systems) item) which doesn't actually have any impact on the code. Sorry, but one thing remains unclear. Ignoring the fact that adding embedded extras to your kernel on a non-embedded system just to get the the VMSPLIT options is (in my opinion) confusing and unlogical, is this step actually needed considering I (according to your advice) would take the default VMSPLIT anyway? What I mean is simply: If I enable HIGHMEM4GB to allow the kernel to use my 2GB of RAM, do I still need to add the embedded options (as you explain above), or is simply using HIGHMEM4GB enough? It's maybe a tough question is ask, but you definitely seem to know exactly what you are talking about ;-) Hope this helps. Is sure does! Any advice to the above question? With that I should be complete I think ;-) Where do you get your information from btw (I'm curious as I didn't find much via Google explaining as clear as you did)? Thanks again, Ralph -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.0 (MingW32) iD8DBQFEmQt3Ct0ZF9kLPvYRAt69AKCe/ClqjzQHMTZ3yvuNQ9sXwVbFsQCeMdwb BREkUr+u9/o9K8ZImMCdJmM= =8vc3 -END PGP SIGNATURE- -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
* Ralph Slooten [EMAIL PROTECTED] [2006-06-21 04:12]: Sorry, but one thing remains unclear. Ignoring the fact that adding embedded extras to your kernel on a non-embedded system just to get the the VMSPLIT options is (in my opinion) confusing and unlogical, is this step actually needed considering I (according to your advice) would take the default VMSPLIT anyway? What I mean is simply: If I enable HIGHMEM4GB to allow the kernel to use my 2GB of RAM, do I still need to add the embedded options (as you explain above), or is simply using HIGHMEM4GB enough? It's maybe a tough question is ask, but you definitely seem to know exactly what you are talking about ;-) Right; the right thing to do here is to not touch VMSPLIT at all, which means there's no reason to be messing around with CONFIG_EMBEDDED. Just set HIGHMEM4GB and be done with it (but, if you're editing a config where you've already done so, make sure that you still have all of the CONFIG_EMBEDDED dependent options set correctly before you unset it: enable every one of the standard kernel features except for the extra pass, and then make sure you have the default 3/1 VMSPLIT) Hope this helps. Is sure does! Any advice to the above question? With that I should be complete I think ;-) Where do you get your information from btw (I'm curious as I didn't find much via Google explaining as clear as you did)? I did some googling about a year and a half ago, when I finally upgraded my desktop from 512MB to 1GB and ran into these issues for the first time, and I've spent some time poking around the kernel sources before. -- David Klempner pgpy6jT8opukm.pgp Description: PGP signature
Re: [gentoo-user] 2GB of RAM
On Wed, 2006-06-21 at 01:21 -0500, David Klempner wrote: * Vladimir G. Ivanovic [EMAIL PROTECTED] [2006-06-20 16:51]: I figured it out. The VMSPLIT options are *not* available on 64-bit systems. (Phew. It's neither encroaching madness nor Alzheimer's.) Yeah... I suppose I wasn't paying close enough attention to what you were saying. :-) Well, it took way longer than I would have wished for me to catch on. You'd think the total absence of any VMSPLIT options in *any* of my saved config files would have been a sufficient hint, but no The VMSPLIT options are about how the kernel uses the 32 bit address space (specifically, what fraction of the address space of each process it reserves for its own use). A large portion of what a 64 bit system gets you is more than 32 bits worth of address space, so I'm fairly sure the entire issue is moot. :-) You're most certainly right. --- Vladimir -- Vladimir G. Ivanovic [EMAIL PROTECTED] -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
What are the names of the config options that change the memory split? I'm running gentoo-sources-2.6.17, and for the life of me, I can't find any config option that deal with memory (and I know they existed: I've set them before.) Thanks. --- Vladimir -- Vladimir G. Ivanovic [EMAIL PROTECTED] -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
On Tue, Jun 20, 2006 at 09:01:26AM -0700, Vladimir G. Ivanovic wrote: What are the names of the config options that change the memory split? I'm running gentoo-sources-2.6.17, and for the life of me, I can't find any config option that deal with memory (and I know they existed: I've set them before.) Are you running a 64 bit kernel? I believe 64 bit architectures don't have this memory limit so low. I can't find it in my kernel config either. Justin -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
# CONFIG_HIGHMEM64G is not set CONFIG_VMSPLIT_3G=y # CONFIG_VMSPLIT_3G_OPT is not set # CONFIG_VMSPLIT_2G is not set # CONFIG_VMSPLIT_1G is not set CONFIG_PAGE_OFFSET=0xC000 CONFIG_HIGHMEM=y On Tue, 20 Jun 2006, Vladimir G. Ivanovic wrote: What are the names of the config options that change the memory split? I'm running gentoo-sources-2.6.17, and for the life of me, I can't find any config option that deal with memory (and I know they existed: I've set them before.) Thanks. --- Vladimir -- Vladimir G. Ivanovic [EMAIL PROTECTED] -- gentoo-user@gentoo.org mailing list -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
Yea, What architecture are you running on? Is it possible that you have some kind of memory interleaving option turned on in your bios that isn't working right because of slight timing differences in the manufacturing of each stick of ram? Are they exactly the same spec (CAS,NS, etc..)? What's the processor? On 6/20/06, Justin R Findlay [EMAIL PROTECTED] wrote: On Tue, Jun 20, 2006 at 09:01:26AM -0700, Vladimir G. Ivanovic wrote: What are the names of the config options that change the memory split? I'm running gentoo-sources-2.6.17, and for the life of me, I can't find any config option that deal with memory (and I know they existed: I've set them before.) Are you running a 64 bit kernel? I believe 64 bit architectures don't have this memory limit so low. I can't find it in my kernel config either. Justin -- gentoo-user@gentoo.org mailing list -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
* Graham Murray [EMAIL PROTECTED] [2006-06-20 12:55]: Justin Piszcz [EMAIL PROTECTED] writes: # CONFIG_HIGHMEM64G is not set CONFIG_VMSPLIT_3G=y # CONFIG_VMSPLIT_3G_OPT is not set # CONFIG_VMSPLIT_2G is not set # CONFIG_VMSPLIT_1G is not set CONFIG_PAGE_OFFSET=0xC000 CONFIG_HIGHMEM=y Is that with x86 and 2.6.17? I had those config options with 2.6.16, but they are not present in 2.6.17. Though looking at /usr/src/linux/arch/i386/Kconfig I cannot see why the option was not offered. For whatever reason, they made prompting about VMSPLIT dependent on CONFIG_EMBEDDED. pgpUHkRbvUVL1.pgp Description: PGP signature
Re: [gentoo-user] 2GB of RAM
On Tue, 2006-06-20 at 14:05 -0500, David Klempner wrote: * Graham Murray [EMAIL PROTECTED] [2006-06-20 12:55]: Justin Piszcz [EMAIL PROTECTED] writes: # CONFIG_HIGHMEM64G is not set CONFIG_VMSPLIT_3G=y # CONFIG_VMSPLIT_3G_OPT is not set # CONFIG_VMSPLIT_2G is not set # CONFIG_VMSPLIT_1G is not set CONFIG_PAGE_OFFSET=0xC000 CONFIG_HIGHMEM=y I do not see *any* of these by grepping through .config. $ for string in highmem vmsplit page_offset; do fgrep -i $string /usr/src/linux-2.6.17-gentoo/.config done $ Since I'm currently running a kernel modules built (yesterday) with this config, I'm pretty confident that the config is OK. Is that with x86 and 2.6.17? I had those config options with 2.6.16, but they are not present in 2.6.17. Though looking at /usr/src/linux/arch/i386/Kconfig I cannot see why the option was not offered. For whatever reason, they made prompting about VMSPLIT dependent on CONFIG_EMBEDDED. This does not seem to be the case on my system Linux scarlatti 2.6.17-gentoo #1 PREEMPT Mon Jun 19 15:28:07 PDT 2006 x86_64 AMD Turion(tm) 64 Mobile Technology MT-32 AuthenticAMD GNU/Linux. All I get when I check CONFIG_EMBEDDED in gconfig is a bunch of questions, which all default to yes, about using futexes, eventpoll, etc. Nothing about memory. Regardless, I'd expect to see those config options listed (but not set) irrespective of whether CONFIG_EMBEDDED is or is not set. The only thing I can conclude is that these configuration options have been removed. (I checked the config resulting from 'make defconfig' as well.) But that doesn't explain why I can't find them in older .configs. $ ls /usr/src/configs/* /usr/src/configs/2.6.14-archck7 /usr/src/configs/2.6.15-ck1 /usr/src/configs/2.6.15-ck1-r1 /usr/src/configs/2.6.15-ck3-r1 /usr/src/configs/2.6.15-gentoo-r4 /usr/src/configs/2.6.15-gentoo-r7 /usr/src/configs/2.6.16-ck2 /usr/src/configs/2.6.16-gentoo-r1 /usr/src/configs/2.6.16-gentoo-r10 /usr/src/configs/2.6.16-gentoo-r2 /usr/src/configs/2.6.16-gentoo-r4 /usr/src/configs/2.6.16-gentoo-r6 /usr/src/configs/2.6.16-gentoo-r8 $ for string in highmem vmsplit page_offset; do fgrep -i $string /usr/src/configs/* done $ I *know* I've seen them before (on my Fedora system?) I must be going mad, or is this what Alzheimer's feels like? --- Vladimir -- Vladimir G. Ivanovic [EMAIL PROTECTED] -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
* Vladimir G. Ivanovic [EMAIL PROTECTED] [2006-06-20 14:45]: Is that with x86 and 2.6.17? I had those config options with 2.6.16, but they are not present in 2.6.17. Though looking at /usr/src/linux/arch/i386/Kconfig I cannot see why the option was not offered. For whatever reason, they made prompting about VMSPLIT dependent on CONFIG_EMBEDDED. This does not seem to be the case on my system It's still in the same place as it was before, and is *definitely* there in both 2.6.17 and 2.6.17-gentoo. (the actual change occurred in rc4) Processor type and features - Memory split Note that CONFIG_EMBEDDED is not in the same place. General setup - Configure standard kernel features pgp5JrLQDgaVa.pgp Description: PGP signature
Re: [gentoo-user] 2GB of RAM
On Tue, 2006-06-20 at 15:01 -0500, David Klempner wrote: * Vladimir G. Ivanovic [EMAIL PROTECTED] [2006-06-20 14:45]: Is that with x86 and 2.6.17? I had those config options with 2.6.16, but they are not present in 2.6.17. Though looking at /usr/src/linux/arch/i386/Kconfig I cannot see why the option was not offered. For whatever reason, they made prompting about VMSPLIT dependent on CONFIG_EMBEDDED. This does not seem to be the case on my system It's still in the same place as it was before, and is *definitely* there in both 2.6.17 and 2.6.17-gentoo. (the actual change occurred in rc4) Processor type and features - Memory split Note that CONFIG_EMBEDDED is not in the same place. General setup - Configure standard kernel features I figured it out. The VMSPLIT options are *not* available on 64-bit systems. (Phew. It's neither encroaching madness nor Alzheimer's.) --- Vladimir -- Vladimir G. Ivanovic [EMAIL PROTECTED] -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 David Klempner wrote: For whatever reason, they made prompting about VMSPLIT dependent on CONFIG_EMBEDDED. I upgraded yesterday to 2.6.17 and also noticed that there was no split option. Not thinking much of it I installed the kernel which works fine, except now /proc/kcore reports 897M, and `free` something to that effect too. So I take it I'm only using just less than 1/2 my RAM now, correct? With 2GB of RAM, Do I now have to enable the embedded option (which gives me a lot more options, most likely all of which I don't need), and then select the 2/2 split, or ? I noticed too that if I select the embedded option, but unselect all new options that come with it I still get the memory split options. Is this the right way to go? It's a 64bit processor compiled and running on a 32bit system. Greetings, Ralph -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.2.2 (GNU/Linux) iD8DBQFEmNRKCt0ZF9kLPvYRAorFAJ98PfKOjoeh+88eeIkZ/LqLI8OSVwCfdQTH Tl88Zk0UWqpPhCq2fNUOhc8= =HzF9 -END PGP SIGNATURE- -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
* Ralph Slooten [EMAIL PROTECTED] [2006-06-19 00:25]: David Klempner wrote: Note that without doing *anything*, with a normal 3G/1G split, you'll actually get 896M. Recent kernels added in a config option to have a 2.75G/1.25G split, which solves this problem; it makes sense to use that if you have 1G of RAM. This option must be really new because I don't have it. I have two 3/1 options, a 2/2 option and a 1/3 option. Either way, I'm now using 2GB. It's one of the two 3/1 options; one of them is a PAGE_OFFSET of 0xC000 (3G) and the other is 0xB000 (2.75G); the latter is suggested for someone using 1GB. (I was making that change myself by hand until they added that option.) In fact, the 2G option is slightly lower than 2G, which is why it works with 2G of RAM. Maybe this is the case, I'm not sure. For testing some other software I upgraded to 2.16.6.16 2 weeks ago (when I still had 1GB) which resulted in the same problem. I then went back to the previous-compiled 2.6.16.5 version which worked flawlessly. It is only now that I have actually rebuilt the 2.6.16.5 kernel (due to RAM upgrade) and am having the same problem. The NVidial kernel and glx (to be sure) were also rebuilt. I did a bit of testing last night before I went to bed and it seems that no matter what options I use in the kernel I'm getting bad performance now from the graphics card. It still gets 4000 fps with glxgears though, so I'm not 100% sure it is the graphics card. The question I was meaning to ask is what the ideal kernel settings should be for 2GB of RAM... from there I'll look for other explanations why the 3d isn't performing well. Do you have performance problems with any other applications? It wouldn't surprise me too much if it's some random library issue that specifically affects that game. Should I use 2/2 *and* highmem, or just 2/2 ? You suggest the highmem does very little, but it's there for a valid reason I take it. If you're doing 2/2, then don't bother with highmem. Without highmem, the kernel maps all of physical memory into its address space; this is naive and fast, but it means that normal processes don't get use of that space. This isn't a problem for most applications, but there are a few that expect the extra address space to be available. A direct result of the 2/2 split is that no single process can, even in theory, (directly) use more than 2G of RAM, because it can't even *address* more than 2G. This would be a more noticeable issue if you had 3G of RAM and did the 1/3 split; at that point, no process could use more than 1G. I've seen long running processes (for example, firefox after a month with several dozen open tabs) use more than that. Highmem adds an extra layer of indirection to solve this problem; it's slightly slower (but, I understand, the cost is minimal) but lets you have your address space back while still being able to use all of your RAM. My suggestion is to use 3/1 with highmem. If you want, you could also use 2/2 without highmem; it would probably be just slightly faster, but could break stuff. Using 2/2 with highmem is (I think) pointless. pgpsDAavPqbVw.pgp Description: PGP signature
Re: [gentoo-user] 2GB of RAM
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Thanks David for the clear answers I'll investigate further. As for the rest of the PC running great with extra RAM ~ it's just UT2004 I have discovered to have an issue here. The 2/2 is what I'm running with at the moment ... seems to be fine. Thanks again, Ralph David Klempner wrote: * Ralph Slooten [EMAIL PROTECTED] [2006-06-19 00:25]: David Klempner wrote: Note that without doing *anything*, with a normal 3G/1G split, you'll actually get 896M. Recent kernels added in a config option to have a 2.75G/1.25G split, which solves this problem; it makes sense to use that if you have 1G of RAM. This option must be really new because I don't have it. I have two 3/1 options, a 2/2 option and a 1/3 option. Either way, I'm now using 2GB. It's one of the two 3/1 options; one of them is a PAGE_OFFSET of 0xC000 (3G) and the other is 0xB000 (2.75G); the latter is suggested for someone using 1GB. (I was making that change myself by hand until they added that option.) In fact, the 2G option is slightly lower than 2G, which is why it works with 2G of RAM. Maybe this is the case, I'm not sure. For testing some other software I upgraded to 2.16.6.16 2 weeks ago (when I still had 1GB) which resulted in the same problem. I then went back to the previous-compiled 2.6.16.5 version which worked flawlessly. It is only now that I have actually rebuilt the 2.6.16.5 kernel (due to RAM upgrade) and am having the same problem. The NVidial kernel and glx (to be sure) were also rebuilt. I did a bit of testing last night before I went to bed and it seems that no matter what options I use in the kernel I'm getting bad performance now from the graphics card. It still gets 4000 fps with glxgears though, so I'm not 100% sure it is the graphics card. The question I was meaning to ask is what the ideal kernel settings should be for 2GB of RAM... from there I'll look for other explanations why the 3d isn't performing well. Do you have performance problems with any other applications? It wouldn't surprise me too much if it's some random library issue that specifically affects that game. Should I use 2/2 *and* highmem, or just 2/2 ? You suggest the highmem does very little, but it's there for a valid reason I take it. If you're doing 2/2, then don't bother with highmem. Without highmem, the kernel maps all of physical memory into its address space; this is naive and fast, but it means that normal processes don't get use of that space. This isn't a problem for most applications, but there are a few that expect the extra address space to be available. A direct result of the 2/2 split is that no single process can, even in theory, (directly) use more than 2G of RAM, because it can't even *address* more than 2G. This would be a more noticeable issue if you had 3G of RAM and did the 1/3 split; at that point, no process could use more than 1G. I've seen long running processes (for example, firefox after a month with several dozen open tabs) use more than that. Highmem adds an extra layer of indirection to solve this problem; it's slightly slower (but, I understand, the cost is minimal) but lets you have your address space back while still being able to use all of your RAM. My suggestion is to use 3/1 with highmem. If you want, you could also use 2/2 without highmem; it would probably be just slightly faster, but could break stuff. Using 2/2 with highmem is (I think) pointless. -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.0 (MingW32) iD8DBQFEllAACt0ZF9kLPvYRAja0AJ4gKhWbGw9uQAWVnsqj/ii9xvPm3wCfZVYE N18blB/cTNxITFmcNMEC+Jw= =VBJE -END PGP SIGNATURE- -- gentoo-user@gentoo.org mailing list
[gentoo-user] 2GB of RAM
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi list, Today I expended my RAM to 2GB (DDR) to my workstation, as apposed to the initial 1GB I had. The RAm added is identical to the initial RAM. Without changing the kernel (2.6.16.x) I still get 1GB available, and digging into the kernel I found the section regarding the High Memory Support and Memory split. I did a bit of googeling, the first page I found (old) said to turn on High Memory Support, however a more recent page (http://linux-vserver.org/Step-by-Step+Guide+2.6) states to leave it off and just change the split to 2/2 to make full use of 2GB of RAM. I tried both ways, but either way I get poor 3D performance from UT2004 when I have this extra memory in. Now I'm confused ;-) It's (kernel's) default is 3G/1G user/kernel split but there seems to be no documentation supplied with my kernel (2.6.16.5). Do any of you have experience with 1GB of RAM, and efficiently getting this to work _well_ on your systems? What ideal settings should I use in my kernel? Are there any downsides to 1GB? With 3G/1G user/kernel split selected, and High Memory Support (off) I get 1GB despite 2GB in the motherboard, even when lilo boots with append=mem=2048M. If I enable the 2/2 option instead I get 2G of RAM. I tested the 2GB with 2x virtual machines (vmware) running each with 512MB ram (iE 1GB in use for vmware) and the system performed still exceptionally well, however UT2004 still sucks when playing (sluggish and screen jolts from time to time like I have too little RAM). Any ideas? Thanks, Ralph -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.2.2 (GNU/Linux) iD8DBQFElZFNCt0ZF9kLPvYRAtI/AJ0ctkVcrWRa1ROC9TwDMlPTpPNRbACdFvVJ wRKCLtGAKSSQMk613mtE/V8= =+Qh0 -END PGP SIGNATURE- -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
On Sun, 18 Jun 2006, Ralph Slooten wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi list, Today I expended my RAM to 2GB (DDR) to my workstation, as apposed to the initial 1GB I had. The RAm added is identical to the initial RAM. Without changing the kernel (2.6.16.x) I still get 1GB available, and digging into the kernel I found the section regarding the High Memory Support and Memory split. I did a bit of googeling, the first page I found (old) said to turn on High Memory Support, however a more recent page (http://linux-vserver.org/Step-by-Step+Guide+2.6) states to leave it off and just change the split to 2/2 to make full use of 2GB of RAM. I tried both ways, but either way I get poor 3D performance from UT2004 when I have this extra memory in. Now I'm confused ;-) It's (kernel's) default is 3G/1G user/kernel split but there seems to be no documentation supplied with my kernel (2.6.16.5). Do any of you have experience with 1GB of RAM, and efficiently getting this to work _well_ on your systems? What ideal settings should I use in my kernel? Are there any downsides to 1GB? With 3G/1G user/kernel split selected, and High Memory Support (off) I get 1GB despite 2GB in the motherboard, even when lilo boots with append=mem=2048M. If I enable the 2/2 option instead I get 2G of RAM. I tested the 2GB with 2x virtual machines (vmware) running each with 512MB ram (iE 1GB in use for vmware) and the system performed still exceptionally well, however UT2004 still sucks when playing (sluggish and screen jolts from time to time like I have too little RAM). Any ideas? Thanks, Ralph What graphics card are you using? Sluggish and screen jolts sound possibly like your graphics are too high for the card. Generally too little ram will result in your HD doing a lot of work during gameplay. -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
* Ralph Slooten [EMAIL PROTECTED] [2006-06-18 12:52]: Today I expended my RAM to 2GB (DDR) to my workstation, as apposed to the initial 1GB I had. The RAm added is identical to the initial RAM. Without changing the kernel (2.6.16.x) I still get 1GB available, and digging into the kernel I found the section regarding the High Memory Support and Memory split. Note that without doing *anything*, with a normal 3G/1G split, you'll actually get 896M. Recent kernels added in a config option to have a 2.75G/1.25G split, which solves this problem; it makes sense to use that if you have 1G of RAM. I did a bit of googeling, the first page I found (old) said to turn on High Memory Support, however a more recent page (http://linux-vserver.org/Step-by-Step+Guide+2.6) states to leave it off and just change the split to 2/2 to make full use of 2GB of RAM. My understanding is that the performance hit from enabling high memory support is actually fairly small; if you have more than 1G (where the fix is unlikely to break anything) it's not worth worrying about. I tried both ways, but either way I get poor 3D performance from UT2004 when I have this extra memory in. (snip) however UT2004 still sucks when playing (sluggish and screen jolts from time to time like I have too little RAM). Any ideas? My guesses is, as has already been suggested, that something is messed up with your video driver. Did you recompile it when you recompile your kernel? Is acceleration still working at all? Do you get the current performance issues either without the extra RAM with a highmem kernel or with the extra RAM without a highmem or 2G/2G kernel? -- David Klempner pgpp5IYaB3O7Y.pgp Description: PGP signature
Re: [gentoo-user] 2GB of RAM
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Steven Susbauer wrote: What graphics card are you using? Sluggish and screen jolts sound possibly like your graphics are too high for the card. Generally too little ram will result in your HD doing a lot of work during gameplay. GeForce 6600/GeForce 6600 GT No, with 1GB of RAM it worked just fine, but with 2GB of RAM it became sluggish. Greetings, Ralph -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.2.2 (GNU/Linux) iD8DBQFEli98Ct0ZF9kLPvYRArkYAJ4mMCR6N0QdQUEQH23zKHJEIodHqgCfV8d4 9zR2QLFdCMjMWlNBAqYOeos= =SMcy -END PGP SIGNATURE- -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] 2GB of RAM
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi David, David Klempner wrote: Note that without doing *anything*, with a normal 3G/1G split, you'll actually get 896M. Recent kernels added in a config option to have a 2.75G/1.25G split, which solves this problem; it makes sense to use that if you have 1G of RAM. This option must be really new because I don't have it. I have two 3/1 options, a 2/2 option and a 1/3 option. Either way, I'm now using 2GB. My understanding is that the performance hit from enabling high memory support is actually fairly small; if you have more than 1G (where the fix is unlikely to break anything) it's not worth worrying about. My guesses is, as has already been suggested, that something is messed up with your video driver. Did you recompile it when you recompile your kernel? Is acceleration still working at all? Do you get the current performance issues either without the extra RAM with a highmem kernel or with the extra RAM without a highmem or 2G/2G kernel? Maybe this is the case, I'm not sure. For testing some other software I upgraded to 2.16.6.16 2 weeks ago (when I still had 1GB) which resulted in the same problem. I then went back to the previous-compiled 2.6.16.5 version which worked flawlessly. It is only now that I have actually rebuilt the 2.6.16.5 kernel (due to RAM upgrade) and am having the same problem. The NVidial kernel and glx (to be sure) were also rebuilt. I did a bit of testing last night before I went to bed and it seems that no matter what options I use in the kernel I'm getting bad performance now from the graphics card. It still gets 4000 fps with glxgears though, so I'm not 100% sure it is the graphics card. The question I was meaning to ask is what the ideal kernel settings should be for 2GB of RAM... from there I'll look for other explanations why the 3d isn't performing well. Should I use 2/2 *and* highmem, or just 2/2 ? You suggest the highmem does very little, but it's there for a valid reason I take it. Thanks for the answers, Ralph -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.2.2 (GNU/Linux) iD8DBQFEljNWCt0ZF9kLPvYRArMnAJ49+k5iZbZGr+UBiPOMtYCDzpJ0QgCghWkt KHDb0KCFbAnyyAQGymJvd70= =Weyw -END PGP SIGNATURE- -- gentoo-user@gentoo.org mailing list
