Re: recommended partition for swap with 0.5 TB memory
On Tue Feb28'23 08:09:24PM, Jeffrey Walton wrote: > From: Jeffrey Walton > Date: Tue, 28 Feb 2023 20:09:24 -0500 > To: Community support for Fedora users > Reply-To: noloa...@gmail.com, Community support for Fedora users > > Subject: Re: recommended partition for swap with 0.5 TB memory > > On Tue, Feb 28, 2023 at 3:02 PM Ranjan Maitra wrote: > > On Tue Feb28'23 01:56:08PM, Richard Shaw wrote: > > > On Tue, Feb 28, 2023 at 1:43 PM Ranjan Maitra wrote: > > > > > > > I am trying to install Fedora on to a new machine that has 0.5 TB RAM. > > > > Hard drives are 256 GB for / and friends, and 2 TB for /home partition. > > > > In > > > > the past, it used to be suggested that swap be twice that of RAM: this > > > > later changed to the same amount, and now it is very unclear (to me) > > > > because I have not tracked the latest recommendations. Anyway, what > > > > would > > > > you suggest? The machine is a Dell Precision 7920 with 28 cores/56 > > > > threads. > > > > > > > > > > By 0.5TB you mean 512GB of ram? Assuming you're installing Fedora 36 or > > > 37, > > > I would just leave the defaults alone, which utilizes swap on zram. So > > > basically it won't use any swap unless needed. You can adjust the amount > > > of > > > memory allowed to be used for swap. > > > > Right, thanks. So, I let the installer pick this up. I usually do a custom > > partitioning, does that mean that I do not declare anything for swap? > > And set swappiness to something low, like 1. There's almost no reason > to allow anything to spill into the swap file with 512GB of RAM. Agreed, but there are 56 threads on this machine. So, if all of them are being used, then the amount of memory is not that much on the average, though I hope to be fine. I currently have a 8y-old 10C (20 thread) machine (originally with 32 GB, went up to 64 GB). At least for some jobs, I was not able to use all threads because of memory requirements. For that machine, I have: $ swapon NAME TYPE SIZE USED PRIO /dev/zram0 partition8G 0B 100 /dev/sdc6 partition 46.6G 0B -2 and $ free totalusedfree shared buff/cache available Mem:65762928 108965661769992 30928 2903280 63914968 Swap: 57215992 057215992 so I guess there is the zram0 there. I also don't see much value in having a lot of swap, unless it is some sort of very short (to be useful) holding operation (that is how my layman's mind likes to think about it). > > In fact, my daily driver has 64GB of RAM, and I set the swap file size > to 4 GB and set swappiness to 1. The 4 GB swap is there for > emergencies, but I don't think it's ever been needed. > Thanks again! Ranjan ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: recommended partition for swap with 0.5 TB memory
On Tue, Feb 28, 2023 at 3:02 PM Ranjan Maitra wrote: > On Tue Feb28'23 01:56:08PM, Richard Shaw wrote: > > On Tue, Feb 28, 2023 at 1:43 PM Ranjan Maitra wrote: > > > > > I am trying to install Fedora on to a new machine that has 0.5 TB RAM. > > > Hard drives are 256 GB for / and friends, and 2 TB for /home partition. In > > > the past, it used to be suggested that swap be twice that of RAM: this > > > later changed to the same amount, and now it is very unclear (to me) > > > because I have not tracked the latest recommendations. Anyway, what would > > > you suggest? The machine is a Dell Precision 7920 with 28 cores/56 > > > threads. > > > > > > > By 0.5TB you mean 512GB of ram? Assuming you're installing Fedora 36 or 37, > > I would just leave the defaults alone, which utilizes swap on zram. So > > basically it won't use any swap unless needed. You can adjust the amount of > > memory allowed to be used for swap. > > Right, thanks. So, I let the installer pick this up. I usually do a custom > partitioning, does that mean that I do not declare anything for swap? And set swappiness to something low, like 1. There's almost no reason to allow anything to spill into the swap file with 512GB of RAM. In fact, my daily driver has 64GB of RAM, and I set the swap file size to 4 GB and set swappiness to 1. The 4 GB swap is there for emergencies, but I don't think it's ever been needed. Jeff ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: recommended partition for swap with 0.5 TB memory
On Tue Feb28'23 03:23:37PM, Richard Shaw wrote: > From: Richard Shaw > Date: Tue, 28 Feb 2023 15:23:37 -0600 > To: Community support for Fedora users > Reply-To: Community support for Fedora users > Subject: Re: recommended partition for swap with 0.5 TB memory > > On Tue, Feb 28, 2023 at 2:48 PM Ranjan Maitra wrote: > > > On Tue Feb28'23 01:56:08PM, Richard Shaw wrote: > > > From: Richard Shaw > > > Date: Tue, 28 Feb 2023 13:56:08 -0600 > > > To: Community support for Fedora users > > > Reply-To: Community support for Fedora users < > > users@lists.fedoraproject.org> > > > Subject: Re: recommended partition for swap with 0.5 TB memory > > > > > > On Tue, Feb 28, 2023 at 1:43 PM Ranjan Maitra wrote: > > > > > > > Hi, > > > > > > > > I am trying to install Fedora on to a new machine that has 0.5 TB RAM. > > > > Hard drives are 256 GB for / and friends, and 2 TB for /home > > partition. In > > > > the past, it used to be suggested that swap be twice that of RAM: this > > > > later changed to the same amount, and now it is very unclear (to me) > > > > because I have not tracked the latest recommendations. Anyway, what > > would > > > > you suggest? The machine is a Dell Precision 7920 with 28 cores/56 > > threads. > > > > > > > > > > By 0.5TB you mean 512GB of ram? Assuming you're installing Fedora 36 or > > 37, > > > I would just leave the defaults alone, which utilizes swap on zram. So > > > basically it won't use any swap unless needed. You can adjust the amount > > of > > > memory allowed to be used for swap. > > > > > > > I decided to let the automatic installer pick up the partition. It > > correctly sets aside 4 TiB (sorry, it was 4TiB, not 2TiB as mentioned > > earlier) for /home, and then 1 GiB for /boot, 600 MiB for /boot/efi, 70 GiB > > for / and leaves aside the rest (as free space). I can adjust the 70 GiB, > > but do I need to keep aside space for the zram? I am unsure about what to > > do with so much free space? > > > > With zram you set a maximum amount of memory which can be used as swap (I > think the default is 50% but it may have a maximum set). How it works is > that it compresses the memory, generally giving around 2X compression. The > CPU cost to compress/decompress is much faster than swapping to disk, > perhaps not as much with modern NVMe drives, but it does help relieve > memory pressure without causing unnecessary writes to your expensive SSDs > :) > Thanks! So, at this point, I will simply increase / to cover around 250 GiB: my plan is to simply copy the first drive to the second for backups. Btw, my sysadmin tells me that he bought 3 4 TiB drives and put it on the card. But during installation, I see only one 4 TiB drive. Is this possible? (These HDDs/SSDs are not RAIDed.) > I was hoping to find something more Fedora centric, but here's the upstream > documentation: > https://github.com/systemd/zram-generator/blob/main/man/zram-generator.conf.md Thanks for this! Best wishes, Ranjan ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: recommended partition for swap with 0.5 TB memory
if whatever you are running on said machine is going to be useless if you are swapping you don't need much swap. The apps I deal with if we get much into swap has severe performance issues and is basically in an outage. I have 72core/1TB ram and have 30GB of swap (pre zram os) The reality is if we are swapping then something/someone screwed up (too many process, process leak, memory leak, machine sized wrong). On Tue, Feb 28, 2023 at 2:48 PM Ranjan Maitra wrote: > > On Tue Feb28'23 01:56:08PM, Richard Shaw wrote: > > From: Richard Shaw > > Date: Tue, 28 Feb 2023 13:56:08 -0600 > > To: Community support for Fedora users > > Reply-To: Community support for Fedora users > > Subject: Re: recommended partition for swap with 0.5 TB memory > > > > On Tue, Feb 28, 2023 at 1:43 PM Ranjan Maitra wrote: > > > > > Hi, > > > > > > I am trying to install Fedora on to a new machine that has 0.5 TB RAM. > > > Hard drives are 256 GB for / and friends, and 2 TB for /home partition. In > > > the past, it used to be suggested that swap be twice that of RAM: this > > > later changed to the same amount, and now it is very unclear (to me) > > > because I have not tracked the latest recommendations. Anyway, what would > > > you suggest? The machine is a Dell Precision 7920 with 28 cores/56 > > > threads. > > > > > > > By 0.5TB you mean 512GB of ram? Assuming you're installing Fedora 36 or 37, > > I would just leave the defaults alone, which utilizes swap on zram. So > > basically it won't use any swap unless needed. You can adjust the amount of > > memory allowed to be used for swap. > > > > > I decided to let the automatic installer pick up the partition. It correctly > sets aside 4 TiB (sorry, it was 4TiB, not 2TiB as mentioned earlier) for > /home, and then 1 GiB for /boot, 600 MiB for /boot/efi, 70 GiB for / and > leaves aside the rest (as free space). I can adjust the 70 GiB, but do I need > to keep aside space for the zram? I am unsure about what to do with so much > free space? > > Many thanks and best wishes, > Ranjan > ___ > users mailing list -- users@lists.fedoraproject.org > To unsubscribe send an email to users-le...@lists.fedoraproject.org > Fedora Code of Conduct: > https://docs.fedoraproject.org/en-US/project/code-of-conduct/ > List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines > List Archives: > https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org > Do not reply to spam, report it: > https://pagure.io/fedora-infrastructure/new_issue ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: recommended partition for swap with 0.5 TB memory
On Tue, Feb 28, 2023 at 2:48 PM Ranjan Maitra wrote: > On Tue Feb28'23 01:56:08PM, Richard Shaw wrote: > > From: Richard Shaw > > Date: Tue, 28 Feb 2023 13:56:08 -0600 > > To: Community support for Fedora users > > Reply-To: Community support for Fedora users < > users@lists.fedoraproject.org> > > Subject: Re: recommended partition for swap with 0.5 TB memory > > > > On Tue, Feb 28, 2023 at 1:43 PM Ranjan Maitra wrote: > > > > > Hi, > > > > > > I am trying to install Fedora on to a new machine that has 0.5 TB RAM. > > > Hard drives are 256 GB for / and friends, and 2 TB for /home > partition. In > > > the past, it used to be suggested that swap be twice that of RAM: this > > > later changed to the same amount, and now it is very unclear (to me) > > > because I have not tracked the latest recommendations. Anyway, what > would > > > you suggest? The machine is a Dell Precision 7920 with 28 cores/56 > threads. > > > > > > > By 0.5TB you mean 512GB of ram? Assuming you're installing Fedora 36 or > 37, > > I would just leave the defaults alone, which utilizes swap on zram. So > > basically it won't use any swap unless needed. You can adjust the amount > of > > memory allowed to be used for swap. > > > > I decided to let the automatic installer pick up the partition. It > correctly sets aside 4 TiB (sorry, it was 4TiB, not 2TiB as mentioned > earlier) for /home, and then 1 GiB for /boot, 600 MiB for /boot/efi, 70 GiB > for / and leaves aside the rest (as free space). I can adjust the 70 GiB, > but do I need to keep aside space for the zram? I am unsure about what to > do with so much free space? > With zram you set a maximum amount of memory which can be used as swap (I think the default is 50% but it may have a maximum set). How it works is that it compresses the memory, generally giving around 2X compression. The CPU cost to compress/decompress is much faster than swapping to disk, perhaps not as much with modern NVMe drives, but it does help relieve memory pressure without causing unnecessary writes to your expensive SSDs :) I was hoping to find something more Fedora centric, but here's the upstream documentation: https://github.com/systemd/zram-generator/blob/main/man/zram-generator.conf.md Thanks, Richard ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: recommended partition for swap with 0.5 TB memory
On Tue Feb28'23 01:56:08PM, Richard Shaw wrote: > From: Richard Shaw > Date: Tue, 28 Feb 2023 13:56:08 -0600 > To: Community support for Fedora users > Reply-To: Community support for Fedora users > Subject: Re: recommended partition for swap with 0.5 TB memory > > On Tue, Feb 28, 2023 at 1:43 PM Ranjan Maitra wrote: > > > Hi, > > > > I am trying to install Fedora on to a new machine that has 0.5 TB RAM. > > Hard drives are 256 GB for / and friends, and 2 TB for /home partition. In > > the past, it used to be suggested that swap be twice that of RAM: this > > later changed to the same amount, and now it is very unclear (to me) > > because I have not tracked the latest recommendations. Anyway, what would > > you suggest? The machine is a Dell Precision 7920 with 28 cores/56 threads. > > > > By 0.5TB you mean 512GB of ram? Assuming you're installing Fedora 36 or 37, > I would just leave the defaults alone, which utilizes swap on zram. So > basically it won't use any swap unless needed. You can adjust the amount of > memory allowed to be used for swap. > I decided to let the automatic installer pick up the partition. It correctly sets aside 4 TiB (sorry, it was 4TiB, not 2TiB as mentioned earlier) for /home, and then 1 GiB for /boot, 600 MiB for /boot/efi, 70 GiB for / and leaves aside the rest (as free space). I can adjust the 70 GiB, but do I need to keep aside space for the zram? I am unsure about what to do with so much free space? Many thanks and best wishes, Ranjan ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: recommended partition for swap with 0.5 TB memory
On Tue Feb28'23 01:56:08PM, Richard Shaw wrote: > From: Richard Shaw > Date: Tue, 28 Feb 2023 13:56:08 -0600 > To: Community support for Fedora users > Reply-To: Community support for Fedora users > Subject: Re: recommended partition for swap with 0.5 TB memory > > On Tue, Feb 28, 2023 at 1:43 PM Ranjan Maitra wrote: > > > Hi, > > > > I am trying to install Fedora on to a new machine that has 0.5 TB RAM. > > Hard drives are 256 GB for / and friends, and 2 TB for /home partition. In > > the past, it used to be suggested that swap be twice that of RAM: this > > later changed to the same amount, and now it is very unclear (to me) > > because I have not tracked the latest recommendations. Anyway, what would > > you suggest? The machine is a Dell Precision 7920 with 28 cores/56 threads. > > > > By 0.5TB you mean 512GB of ram? Assuming you're installing Fedora 36 or 37, > I would just leave the defaults alone, which utilizes swap on zram. So > basically it won't use any swap unless needed. You can adjust the amount of > memory allowed to be used for swap. > Right, thanks. So, I let the installer pick this up. I usually do a custom partitioning, does that mean that I do not declare anything for swap? Thanks very much! Best wishes, Ranjan ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
Re: recommended partition for swap with 0.5 TB memory
On Tue, Feb 28, 2023 at 1:43 PM Ranjan Maitra wrote: > Hi, > > I am trying to install Fedora on to a new machine that has 0.5 TB RAM. > Hard drives are 256 GB for / and friends, and 2 TB for /home partition. In > the past, it used to be suggested that swap be twice that of RAM: this > later changed to the same amount, and now it is very unclear (to me) > because I have not tracked the latest recommendations. Anyway, what would > you suggest? The machine is a Dell Precision 7920 with 28 cores/56 threads. > By 0.5TB you mean 512GB of ram? Assuming you're installing Fedora 36 or 37, I would just leave the defaults alone, which utilizes swap on zram. So basically it won't use any swap unless needed. You can adjust the amount of memory allowed to be used for swap. Thanks, Richard ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
recommended partition for swap with 0.5 TB memory
Hi, I am trying to install Fedora on to a new machine that has 0.5 TB RAM. Hard drives are 256 GB for / and friends, and 2 TB for /home partition. In the past, it used to be suggested that swap be twice that of RAM: this later changed to the same amount, and now it is very unclear (to me) because I have not tracked the latest recommendations. Anyway, what would you suggest? The machine is a Dell Precision 7920 with 28 cores/56 threads. Many thanks for any suggestions, and best wishes, Ranjan ___ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
