Re: [gentoo-user] Performance problem (slow hard drive?)
On Wednesday 06 April 2005 04:03, Ow Mun Heng wrote: > On Mon, 2005-04-04 at 17:35 +0200, Volker Armin Hemmann wrote: > > I also experimented > > a little bit with swsusp (without much success), > > try suspend2 then.. 15 secs from running to hibernate thanks, swsusp also shut down my box in less than 30 sec, but was never able to recover it. So .. I stoped experimenting and do clean boots ... at least hw-faults are showing up fast this way. -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
On Mon, 2005-04-04 at 17:35 +0200, Volker Armin Hemmann wrote: > I also experimented > a little bit with swsusp (without much success), try suspend2 then.. 15 secs from running to hibernate -- Ow Mun Heng Gentoo/Linux on DELL D600 1.4Ghz 98% Microsoft(tm) Free!! Neuromancer 10:03:05 up 1 day, 13:58, 5 users, load average: 0.15, 0.29, 0.27 -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Shawn Singh wrote: >One thing that I noticed with my installs of Linux is that different >filesystems seem to perform differently...ie. my installst that are >using Reiserfs seem to have quicker reads and writes than my installs >that are using ext2 or ext3... > > Indeed. I just converted my root filesystem from xfs to reiserfs 3.6. My root filesystem contains ~375000 files, and scanning that many files with xfs took a bit over 10 minutes. It takes less than 6 minutes with reiserfs. -Richard -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
One thing that I noticed with my installs of Linux is that different filesystems seem to perform differently...ie. my installst that are using Reiserfs seem to have quicker reads and writes than my installs that are using ext2 or ext3... Also, another thing that I noticed, is that I trim down services that I don't absolutely need to be running..and that seems to help with performance. The nice thing about Gentoo is that a lot of stuff doesn't get started by default. :) I hope this helps. Shawn On Apr 4, 2005 8:40 AM, Covington, Chris <[EMAIL PROTECTED]> wrote: > > I've been experiencing performance problems in my laptop > > (Acer Aspire 1522WLMi). > > How much memory (RAM) do you have? That could be the bottleneck. > > --- > Chris Covington > IT > Plus One Health Management > 75 Maiden Lane Suite 801 > NY, NY 10038 > 646-312-6269 > http://www.plusoneactive.com > > -- > [email protected] mailing list > > -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
On Monday 04 April 2005 17:31, Jose Gonzalez Gomez wrote: > > I'm developing in Java/J2EE using Eclipse, Maven, JBoss and KDE, with > 512Mb of main memory and 1Gb of swap. Assuming this is the problem, is > there any other solution than buying a 1Gb memory module and throwing > away one of my 256Mb modules (I have no free slot)??? Can't the swap > performance be improved in any way? hm, you could search your favorite lkml-archive for 'swap' and 'performance' .. there were some patches in the last 4 month, but I do know nothing about them ;) -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
On Monday 04 April 2005 21:34, Ivan Yosifov wrote: > Try setting vm.swappiness = 0 in /etc/sysctl.conf . The default is 60. > The smaller the value, the more reluctant the kernel will be to swap. > Range is 0...100 . thanks, I know about swappiness: energy portage # cat /proc/sys/vm/swappiness 10 10 is not much better than 60, but 100 is much worse. The problem is not swapping itself, it is, that always the wrong stuff ends in the swapspace and it is so dead slow, as if every single bit is personally transfered first class, before the next on is going over the cable ... -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Graham Murray wrote: >It is not just swap which causes the system to become slow. I find >that it does the same when running 'emerge sync' and vmstat shows no >or only very light swap activity. Yet top shows >80% (often in the >upper 95-98%) CPU in 'Wait for I/O'. My hard disks have DMA enabled >and 'hdparm -i' shows they are all using UDMA4, so why should the I/O >be consuming so much CPU? I would expect it to just start the disk >transfers then suspend the process (waiting for the DMA transfer to >complete) and allocate the CPU to running another process which is not >waiting for disk I/O. > My understanding of the 'wait for I/O' (WIO) state is that it _doesn't_ consume CPU cycles. That is, if I run a process (like dd if=/dev/hda of=/dev/null bs=32k), if the IO is really consuming CPU cycles, then the CPU should not be in an idle loop and I should notice my CPU fans spin up and extra heat coming from my laptop. This doesn't happen, even though my system shows 80% WIO. However, if while that dd command is running, I also start "gzip -9 /dev/null", the gzip command consumes 90% of the CPU, taking over all of the time that was previously in WIO. So I am pretty sure that other processes are able to use the processor while in the WIO state. I think it is just and indication that the processor has been idled, because anything that would like to run cannot due to needing IO to complete. That said, the system will seem slow, because almost everything has to do _some_ IO to the disk to be useful. And swapping even a few pages in/out would delay the whole system. -Richard -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Jose Gonzalez Gomez wrote: >packet root # hdparm -tT /dev/hda > >/dev/hda: > Timing cached reads: 2216 MB in 2.00 seconds = 1107.06 MB/sec > Timing buffered disk reads: 76 MB in 3.03 seconds = 25.06 MB/sec > > Unfortunately, disk throughput is an almost useless measure of performance for your situation. This is because it is really the average seek time that is killing you, not throughput. And that toshiba drive is running at 4200rpm, with an average seek time of ~19ms. Or put in other words, that means your performance when needing to access different areas of the disk simultaneously (for example, the kernel swapping memory while an app is trying to read or write files) is about 50 IOs/sec. My suggestions (in order of least to most expensive): 1. Play with the 'swappiness' parameter (google it). 2. Reduce the amount of swap, and make sure it is located adjacent to your root partition (or, if you use a /usr partition, put it next to /usr). 3. Partition your disk, if you don't already. Making partitions helps to keep related files close together, reducing the time it takes to seek from one to the other, and reduces the effect of fragmentation in Linux. If you don't need all 80GB, you could even leave the last 20-30% unallocated, which is typically the worst performing section of the disk (for throughput). 4. Purchase a new disk. The 60GB 7200rpm Hitachi disks are the fastest disks available for a laptop today, with an average seek time of ~14ms. 5. Upgrade memory (1G recommended). A word on partitioning: I have 2 of those Hitachi disks in my laptop, in a raid0 configuration. After a small boot partition, swap (2G) is the next thing on the disks, followed by 20G of root, followed by 5G of var, 2G of tmp, and 50G of home. The last 32G of the array is not allocated to anything in particular. With 2 processes accessing root & swap, I run over 120 IOs/sec. If those same two processes have to randomly access the entire array, the performance drops to 94 IOs/sec. Hope this helps. -Richard -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Try setting vm.swappiness = 0 in /etc/sysctl.conf . The default is 60. The smaller the value, the more reluctant the kernel will be to swap. Range is 0...100 . On Mon, 2005-04-04 at 17:35 +0200, Volker Armin Hemmann wrote: > Hi, > On Monday 04 April 2005 17:24, Christoph Gysin wrote: > > Volker Armin Hemmann wrote: > > > How do I get my performance back? Easy: swapoff -a && swapon -a and > > > bingo, KDE is lighting fast again. > > > > What about not using swap at all? With 1 gig RAM on your desktop machine, > > are you ever going to fill up your RAM entirely? If swapping on linux > > sucks, disable it. > > > > Of course this is not recommended on a production server ;-) > > > > Christoph > > because when I compile HUGEAPP I sometimes need some swap. I also > experimented > a little bit with swsusp (without much success), and I think it is better to > have a slowdown, than the oom-killer killing the wrong app ... > > -- > [email protected] mailing list > > -- Ivan Yosifov. -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
On Apr 4, 2005 5:49 PM, Hans-Werner Hilse <[EMAIL PROTECTED]> wrote: > Hi, > > On Mon, 4 Apr 2005 10:55:24 +0200 Jose Gonzalez Gomez > <[EMAIL PROTECTED]> wrote: > > > I've been experiencing performance problems in my laptop (Acer Aspire > > 1522WLMi). I have the feeling that the problem is related to hard > > drive performance, as whenever I do some I/O intensive task (mainly > > tested compiling Java code) my system performance goes down, and > > switching to any other application takes a lot (hard drive performance > > problem while doing swapping?). I hasn't been able to solve it, > > although I've read doco and tried tweaking the hd peformance with > > hdparm. > > Do you have > - preemption enabled for that kernel (should allow to switch apps faster > when swapping is in progress) No, I'll try to enable it... > - some logical layers between the hard disk and the swap device (DM, other > block dev abstractions, file system...)? No that I'm aware off, just followed the handbook, so I have a dedicated swap partition. > - enabled a _reasonable_ io scheduler for the kernel? Where can I check that? Any kernel option? > - some memory eaters running (UML, VMware...)? Do you consider several Java virtual machines a memory eater? ;o) If yes then I guess so... I have a JBoss server running, Eclipse, and I use Maven to compile and deploy my Java (J2EE) application > - checked if thermal throttling may cause that? Umm... no, but I didn't think of that as I always noticed disk activity whenever my system slowed down... > > HWH -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Hi, On Mon, 4 Apr 2005 10:55:24 +0200 Jose Gonzalez Gomez <[EMAIL PROTECTED]> wrote: > I've been experiencing performance problems in my laptop (Acer Aspire > 1522WLMi). I have the feeling that the problem is related to hard > drive performance, as whenever I do some I/O intensive task (mainly > tested compiling Java code) my system performance goes down, and > switching to any other application takes a lot (hard drive performance > problem while doing swapping?). I hasn't been able to solve it, > although I've read doco and tried tweaking the hd peformance with > hdparm. Do you have - preemption enabled for that kernel (should allow to switch apps faster when swapping is in progress) - some logical layers between the hard disk and the swap device (DM, other block dev abstractions, file system...)? - enabled a _reasonable_ io scheduler for the kernel? - some memory eaters running (UML, VMware...)? - checked if thermal throttling may cause that? HWH -- This message is made of 100% recycled bits and bytes! -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Volker Armin Hemmann <[EMAIL PROTECTED]> writes: > swap is incredibly slow on linux. As soon as you are hitting swap, your box > is > dead slow. It is not just swap which causes the system to become slow. I find that it does the same when running 'emerge sync' and vmstat shows no or only very light swap activity. Yet top shows >80% (often in the upper 95-98%) CPU in 'Wait for I/O'. My hard disks have DMA enabled and 'hdparm -i' shows they are all using UDMA4, so why should the I/O be consuming so much CPU? I would expect it to just start the disk transfers then suspend the process (waiting for the DMA transfer to complete) and allocate the CPU to running another process which is not waiting for disk I/O. -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Hi, On Monday 04 April 2005 17:24, Christoph Gysin wrote: > Volker Armin Hemmann wrote: > > How do I get my performance back? Easy: swapoff -a && swapon -a and > > bingo, KDE is lighting fast again. > > What about not using swap at all? With 1 gig RAM on your desktop machine, > are you ever going to fill up your RAM entirely? If swapping on linux > sucks, disable it. > > Of course this is not recommended on a production server ;-) > > Christoph because when I compile HUGEAPP I sometimes need some swap. I also experimented a little bit with swsusp (without much success), and I think it is better to have a slowdown, than the oom-killer killing the wrong app ... -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
On Apr 4, 2005 4:44 PM, Volker Armin Hemmann <[EMAIL PROTECTED]> wrote: > Hi, > > On Monday 04 April 2005 10:55, Jose Gonzalez Gomez wrote: > > Hi there, > > > > I've been experiencing performance problems in my laptop (Acer Aspire > > 1522WLMi). I have the feeling that the problem is related to hard > > drive performance, as whenever I do some I/O intensive task (mainly > > tested compiling Java code) my system performance goes down, and > > switching to any other application takes a lot (hard drive performance > > problem while doing swapping?). I hasn't been able to solve it, > > although I've read doco and tried tweaking the hd peformance with > > hdparm. > > swap is incredibly slow on linux. As soon as you are hitting swap, your box is > dead slow. > > And this is not, because the swapping mechanism is stupid (it seems to be > stupid for me, because it always swaps out the wrong things), but because how > it reads the data back (if I remember right, there were some discussions on > lkml in january and february about low swap performance). > > For example: > I have 512mb ram, and this is enough. Really. But to be safe, I have 1gig > swap. > > So, I have KDE 3.4 with a lot of eye-candy running, some konqueror-windows > with tabs, kmail, swap is not used. > > I download BIGFILE (like some linux-isos), suddenly KDE is dead slow. Ok, the > harddisk is doing a lot of stuff, so it is normal for everything that wants > to load something is slow, but hey, the download has ended, BIGFILE lies > around on my harddisk, but KDE is still mostly swapped out and the > caches&buffers are huge(Reducing swappiness to 10 does not help)? What is > that? And why does it not get better over the next minutes/hours? > > How do I get my performance back? Easy: swapoff -a && swapon -a and bingo, KDE > is lighting fast again. > > Something is very broken in swapland, but at least the workaround is easy ... I tried the swapoff/swapon command but took around a minute or so to complete in my machine, so I guess this may be a workaround in some situations, but it's not suitable in my case: I get the slowdown everytime I execute Maven to compile and deploy the application I'm developing in my local test environment. Deactivating and reactivating swap every time I compile would be overkill. I'm developing in Java/J2EE using Eclipse, Maven, JBoss and KDE, with 512Mb of main memory and 1Gb of swap. Assuming this is the problem, is there any other solution than buying a 1Gb memory module and throwing away one of my 256Mb modules (I have no free slot)??? Can't the swap performance be improved in any way? Thanks, best regards Jose -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Volker Armin Hemmann wrote: How do I get my performance back? Easy: swapoff -a && swapon -a and bingo, KDE is lighting fast again. What about not using swap at all? With 1 gig RAM on your desktop machine, are you ever going to fill up your RAM entirely? If swapping on linux sucks, disable it. Of course this is not recommended on a production server ;-) Christoph -- echo mailto: NOSPAM !#$.'<*>'|sed 's. ..'|tr "<*> !#:2" [EMAIL PROTECTED] -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
Hi, On Monday 04 April 2005 10:55, Jose Gonzalez Gomez wrote: > Hi there, > > I've been experiencing performance problems in my laptop (Acer Aspire > 1522WLMi). I have the feeling that the problem is related to hard > drive performance, as whenever I do some I/O intensive task (mainly > tested compiling Java code) my system performance goes down, and > switching to any other application takes a lot (hard drive performance > problem while doing swapping?). I hasn't been able to solve it, > although I've read doco and tried tweaking the hd peformance with > hdparm. swap is incredibly slow on linux. As soon as you are hitting swap, your box is dead slow. And this is not, because the swapping mechanism is stupid (it seems to be stupid for me, because it always swaps out the wrong things), but because how it reads the data back (if I remember right, there were some discussions on lkml in january and february about low swap performance). For example: I have 512mb ram, and this is enough. Really. But to be safe, I have 1gig swap. So, I have KDE 3.4 with a lot of eye-candy running, some konqueror-windows with tabs, kmail, swap is not used. I download BIGFILE (like some linux-isos), suddenly KDE is dead slow. Ok, the harddisk is doing a lot of stuff, so it is normal for everything that wants to load something is slow, but hey, the download has ended, BIGFILE lies around on my harddisk, but KDE is still mostly swapped out and the caches&buffers are huge(Reducing swappiness to 10 does not help)? What is that? And why does it not get better over the next minutes/hours? How do I get my performance back? Easy: swapoff -a && swapon -a and bingo, KDE is lighting fast again. Something is very broken in swapland, but at least the workaround is easy ... -- [email protected] mailing list
Re: [gentoo-user] Performance problem (slow hard drive?)
On Monday 04 April 2005 16:55, Jose Gonzalez Gomez wrote:
> Hi there,
>
> I've been experiencing performance problems in my laptop (Acer Aspire
> 1522WLMi). I have the feeling that the problem is related to hard
> drive performance, as whenever I do some I/O intensive task (mainly
> tested compiling Java code) my system performance goes down, and
> switching to any other application takes a lot (hard drive performance
> problem while doing swapping?). I hasn't been able to solve it,
> although I've read doco and tried tweaking the hd peformance with
> hdparm.
>
> Here is the info for my system, notice the unknown devices in lspci
> output (any missing driver in kernel?) and the "BuffType=unknown,
> BuffSize=0kB" in hdparm output (is my hard drive using its 8Mb
> internal buffer???):
>
> Portage 2.0.51.19 (default-linux/amd64/2004.3, gcc-3.4.2,
> glibc-2.3.4.20041102-r1, 2.6.9-gentoo-r14 x86_64)
> System uname: 2.6.9-gentoo-r14 x86_64 AMD Athlon(tm) 64 Processor 3000+
>
> packet root # lspci
> :00:00.0 Host bridge: VIA Technologies, Inc.: Unknown device 0204
> :00:00.1 Host bridge: VIA Technologies, Inc.: Unknown device 1204
> :00:00.2 Host bridge: VIA Technologies, Inc.: Unknown device 2204
> :00:00.3 Host bridge: VIA Technologies, Inc. K8M800
> :00:00.4 Host bridge: VIA Technologies, Inc.: Unknown device 4204
> :00:00.7 Host bridge: VIA Technologies, Inc. K8M800
> :00:01.0 PCI bridge: VIA Technologies, Inc. VT8237 PCI bridge [K8T800
> South] :00:0a.0 Ethernet controller: Linksys, A Division of Cisco
> Systems [AirConn] INPROCOMM IPN 2220 Wireless LAN Adapter (rev 01)
> :00:0b.0 CardBus bridge: Texas Instruments PCI7420 CardBus Controller
> :00:0b.1 CardBus bridge: Texas Instruments PCI7420 CardBus Controller
> :00:0b.2 FireWire (IEEE 1394): Texas Instruments PCI7x20
> 1394a-2000 OHCI Two-Port PHY/Link-Layer Controller
> :00:0c.0 Ethernet controller: Realtek Semiconductor Co., Ltd.
> RTL-8169 Gigabit Ethernet (rev 10)
> :00:10.0 USB Controller: VIA Technologies, Inc. VT82x UHCI USB
> 1.1 Controller (rev 80)
> :00:10.1 USB Controller: VIA Technologies, Inc. VT82x UHCI USB
> 1.1 Controller (rev 80)
> :00:10.2 USB Controller: VIA Technologies, Inc. VT82x UHCI USB
> 1.1 Controller (rev 80)
> :00:10.3 USB Controller: VIA Technologies, Inc. USB 2.0 (rev 82)
> :00:11.0 ISA bridge: VIA Technologies, Inc. VT8235 ISA Bridge
> :00:11.1 IDE interface: VIA Technologies, Inc.
> VT82C586A/B/VT82C686/A/B/VT823x/A/C PIPC Bus Master IDE (rev 06)
> :00:11.5 Multimedia audio controller: VIA Technologies, Inc.
> VT8233/A/8235/8237 AC97 Audio Controller (rev 50)
> :00:11.6 Communication controller: VIA Technologies, Inc. AC'97
> Modem Controller (rev 80)
> :00:18.0 Host bridge: Advanced Micro Devices [AMD] K8
> [Athlon64/Opteron] HyperTransport Technology Configuration
> :00:18.1 Host bridge: Advanced Micro Devices [AMD] K8
> [Athlon64/Opteron] Address Map
> :00:18.2 Host bridge: Advanced Micro Devices [AMD] K8
> [Athlon64/Opteron] DRAM Controller
> :00:18.3 Host bridge: Advanced Micro Devices [AMD] K8
> [Athlon64/Opteron] Miscellaneous Control
> :01:00.0 VGA compatible controller: nVidia Corporation NV36
> [GeForce FX Go5700] (rev a1)
>
> packet root # grep VIA /usr/src/linux/.config
> CONFIG_BLK_DEV_VIA82CXXX=y
> CONFIG_SCSI_SATA_VIA=m
> CONFIG_VIA_RHINE=m
> # CONFIG_VIA_RHINE_MMIO is not set
> # CONFIG_VIA_VELOCITY is not set
> # CONFIG_I2C_VIA is not set
> CONFIG_I2C_VIAPRO=m
> CONFIG_SENSORS_VIA686A=m
>
> packet root # hdparm -vid /dev/hda
>
> /dev/hda:
> multcount= 16 (on)
> IO_support = 1 (32-bit)
> unmaskirq= 1 (on)
> using_dma= 1 (on)
> keepsettings = 0 (off)
> readonly = 0 (off)
> readahead= 256 (on)
> geometry = 65535/16/63, sectors = 80026361856, start = 0
>
> Model=TOSHIBA MK8025GAS, FwRev=KA023A, SerialNo=74631490S
> Config={ Fixed }
> RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=48
> BuffType=unknown, BuffSize=0kB, MaxMultSect=16, MultSect=16
> CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=156301488
> IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
> PIO modes: pio0 pio1 pio2 pio3 pio4
> DMA modes: sdma0 sdma1 sdma2 mdma0 mdma1 mdma2
> UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5
> AdvancedPM=yes: unknown setting WriteCache=enabled
> Drive conforms to: device does not report version:
>
> * signifies the current active mode
>
> packet root # hdparm -tT /dev/hda
>
> /dev/hda:
> Timing cached reads: 2216 MB in 2.00 seconds = 1107.06 MB/sec
> Timing buffered disk reads: 76 MB in 3.03 seconds = 25.06 MB/sec
>
>
> Any suggestions?
>
> Thanks in advance, best regards
> Jose
> --
> [email protected] mailing list
I think your hd is not slow from your hdparm -tT result.
And hdparm often says "unknown" type of cache, it doesn't matter.
--
Regards,
Jan
Computer Science & Engineering Department,
College
Re: [gentoo-user] Performance problem (slow hard drive?)
> I've been experiencing performance problems in my laptop > (Acer Aspire 1522WLMi). How much memory (RAM) do you have? That could be the bottleneck. --- Chris Covington IT Plus One Health Management 75 Maiden Lane Suite 801 NY, NY 10038 646-312-6269 http://www.plusoneactive.com -- [email protected] mailing list
