4 ms·

“Le9” Strives to Make Linux Usable on Systems with Small Amounts of RAM

47 points by watchdogtimer 5y ago

usr1106 5y ago
> According to the Phoronix reader involved with the Le9 work, he's reportedly able to run Mozilla Firefox with 37 tabs as well as having Skype, Discord, two PDFs, and LibreOffice all running on an aging decade old system with just 2GB of RAM. What does the patch do? According to my very quick read it will lock some pages in the cache. And because they are talking about a swapless system it means it that the system will kill processes earlier because it runs out of memory earlier. Their viewpoint is that killing some process is less damage than have the everything running but thrashing and thereby unusable for the normal user. That all makes some sense to me. Except that it absolutely does not explain how 37 Firefox tabs, Skype (which is a Chromium) and whatever they list there could suddenly run. The patch does not magically add available memory. Something does not match in that story.
- vondur 5y ago
  I saw the article with the user who had the system in question, it didn't make it to the front page. I believe they were using some memory compression that made virtual memory far faster.
- ValdikSS 5y ago
  https://notes.valdikss.org.ru/linux-for-old-pc-from-2007/en/ https://notes.valdikss.org.ru/linux-for-old-pc-from-2007/en/ The patch prevents eviction of file cache from the RAM, which, when using with zram, makes the system very fast when it is swapping. On regular Linux, when the system is low on RAM, file cache is evicted so quickly and is re-read from the (slow) HDD relatively slowly, that's why the software "lags" (it can't reload the code and resources fast enough to stay fully responsive). However, with this patch file cache stay in RAM until absolutely necessary to evict it. This GREATLY increases system responsiveness. Even on my old PC from 2007 from the article, swapping hundreds of megabytes to zram is almost unnoticeable process with the patch. The software is so responsive like nothing happens. Without the patch the PC is uncomfortably slow at times. Swapping process is definitely noticeable, the system may become unresponsive for several seconds (even the mouse doesn't move). The speedup, however, is a bit of side effect of the patch. It was designed to prevent hard thrashing when the system only evicts and reloads data from the disk for indefinite amount of time. Watch the video in the linked article above. There's also a LiveCD ISO file to try the patch effect without installing the system/the patched kernel.
  - usr1106 5y ago
    Ok, so zram is the magic "memory grower". That's orthogonal to the kernel patch and not really swapless like in the patch description. One of my low end Linux phones uses zram. The phone is slow under load, but I have not done any analysis what is the bottleneck. I have smaller eMMC-based laptops with not much RAM (Don't remember whether 1 or 2 GB) Not in heavy use, but I'll bookmark your reply for testing on one of those. It feels pretty wasteful to use 4 or 8 GB for some basic Web browsing these days. Resource efficiency like American cars from the late 1950s...
    - ValdikSS 5y ago
      No-no, le9 is very useful both with swap (physical or zram) and without. With zram it makes swapping process seamless (no lags when swapping), with physical swap on HDD it makes it a bit softer (on regular kernel both swapping and file reloading upon swapping occurs, making the process even more slower; with le9 it's mostly only swapping), and without swap it prevents hard thrashing and freeze of the PC, (additionally) making OOM killer to trigger much earlier than it usually triggers.
tablespoon 5y ago
> According to the Phoronix reader involved with the Le9 work, he's reportedly able to run Mozilla Firefox with 37 tabs as well as having Skype, Discord, two PDFs, and LibreOffice all running on an aging decade old system with just 2GB of RAM. I recall having more than 37 Netscape windows open on a system with 64MB, back in the 90s.
- justinsaccount 5y ago
  People like to forget that having 37 windows open with netscape was possible, but it would regularly crash and take all 37 windows with it. Also, all 37 tabs were likely displaying pages that looked like HN or lite.cnn.com Software isn't really that bloated, it's the content. In the 90s if you had a video on a website it was things like 320x240 at 15fps. If you had a jpeg it was probably 640x480, and there might have been one or two on a page. If I load https://flickr.com/ https://flickr.com/ it sends down a 2000x1333 background image that is almost 700K. On my dialup connection in the 90s that would have taken almost 5 minutes to load. The image likely takes 5MB of ram (or at least gpu memory?) to display. Looking at flickr snapshot from 2004, the entire page is 300K. https://web.archive.org/web/20040701020748/http://flickr.com/ https://web.archive.org/web/20040701020748/http://flickr.com... Sure, some JS stuff is bloated, but you can remove all the JS in the world and it won't change the fact that images are 10 times the size that they used to be. The one thing that likely uses more resources is the per-tab sandboxing browsers do now.
  - tablespoon 5y ago
    > People like to forget that having 37 windows open with netscape was possible, but it would regularly crash and take all 37 windows with it. Also, all 37 tabs were likely displaying pages that looked like HN or lite.cnn.com And that was close to paradise, in comparison with the modern web. > Software isn't really that bloated, it's the content. It doesn't have to be one or the other, it can be both.
- MR4D 5y ago
  Ouch. Something tells me that in the future on our personal computers we will be running virtual windowing systems (KDE, GTK, etc), which will make this both better and worse. That GTK (and firefox) take so much more memory to run still amazes me. If I had the time, I'd love to run an old version of Firefox on a current Linux set up just to see what would happen. --------- EDIT - I have "GTK" above, because it covers not only Gnome, but also XFCE, etc.

47 points by watchdogtimer 5y ago

> According to the Phoronix reader involved with the Le9 work, he's reportedly able to run Mozilla Firefox with 37 tabs as well as having Skype, Discord, two PDFs, and LibreOffice all running on an aging decade old system with just 2GB of RAM. What does the patch do? According to my very quick read it will lock some pages in the cache. And because they are talking about a swapless system it means it that the system will kill processes earlier because it runs out of memory earlier. Their viewpoint is that killing some process is less damage than have the everything running but thrashing and thereby unusable for the normal user. That all makes some sense to me. Except that it absolutely does not explain how 37 Firefox tabs, Skype (which is a Chromium) and whatever they list there could suddenly run. The patch does not magically add available memory. Something does not match in that story.

vondur 5y ago
I saw the article with the user who had the system in question, it didn't make it to the front page. I believe they were using some memory compression that made virtual memory far faster.
ValdikSS 5y ago
https://notes.valdikss.org.ru/linux-for-old-pc-from-2007/en/ https://notes.valdikss.org.ru/linux-for-old-pc-from-2007/en/ The patch prevents eviction of file cache from the RAM, which, when using with zram, makes the system very fast when it is swapping. On regular Linux, when the system is low on RAM, file cache is evicted so quickly and is re-read from the (slow) HDD relatively slowly, that's why the software "lags" (it can't reload the code and resources fast enough to stay fully responsive). However, with this patch file cache stay in RAM until absolutely necessary to evict it. This GREATLY increases system responsiveness. Even on my old PC from 2007 from the article, swapping hundreds of megabytes to zram is almost unnoticeable process with the patch. The software is so responsive like nothing happens. Without the patch the PC is uncomfortably slow at times. Swapping process is definitely noticeable, the system may become unresponsive for several seconds (even the mouse doesn't move). The speedup, however, is a bit of side effect of the patch. It was designed to prevent hard thrashing when the system only evicts and reloads data from the disk for indefinite amount of time. Watch the video in the linked article above. There's also a LiveCD ISO file to try the patch effect without installing the system/the patched kernel.
- usr1106 5y ago
  Ok, so zram is the magic "memory grower". That's orthogonal to the kernel patch and not really swapless like in the patch description. One of my low end Linux phones uses zram. The phone is slow under load, but I have not done any analysis what is the bottleneck. I have smaller eMMC-based laptops with not much RAM (Don't remember whether 1 or 2 GB) Not in heavy use, but I'll bookmark your reply for testing on one of those. It feels pretty wasteful to use 4 or 8 GB for some basic Web browsing these days. Resource efficiency like American cars from the late 1950s...
  - ValdikSS 5y ago
    No-no, le9 is very useful both with swap (physical or zram) and without. With zram it makes swapping process seamless (no lags when swapping), with physical swap on HDD it makes it a bit softer (on regular kernel both swapping and file reloading upon swapping occurs, making the process even more slower; with le9 it's mostly only swapping), and without swap it prevents hard thrashing and freeze of the PC, (additionally) making OOM killer to trigger much earlier than it usually triggers.

tablespoon 5y ago

> According to the Phoronix reader involved with the Le9 work, he's reportedly able to run Mozilla Firefox with 37 tabs as well as having Skype, Discord, two PDFs, and LibreOffice all running on an aging decade old system with just 2GB of RAM. I recall having more than 37 Netscape windows open on a system with 64MB, back in the 90s.

justinsaccount 5y ago
People like to forget that having 37 windows open with netscape was possible, but it would regularly crash and take all 37 windows with it. Also, all 37 tabs were likely displaying pages that looked like HN or lite.cnn.com Software isn't really that bloated, it's the content. In the 90s if you had a video on a website it was things like 320x240 at 15fps. If you had a jpeg it was probably 640x480, and there might have been one or two on a page. If I load https://flickr.com/ https://flickr.com/ it sends down a 2000x1333 background image that is almost 700K. On my dialup connection in the 90s that would have taken almost 5 minutes to load. The image likely takes 5MB of ram (or at least gpu memory?) to display. Looking at flickr snapshot from 2004, the entire page is 300K. https://web.archive.org/web/20040701020748/http://flickr.com/ https://web.archive.org/web/20040701020748/http://flickr.com... Sure, some JS stuff is bloated, but you can remove all the JS in the world and it won't change the fact that images are 10 times the size that they used to be. The one thing that likely uses more resources is the per-tab sandboxing browsers do now.
- tablespoon 5y ago
  > People like to forget that having 37 windows open with netscape was possible, but it would regularly crash and take all 37 windows with it. Also, all 37 tabs were likely displaying pages that looked like HN or lite.cnn.com And that was close to paradise, in comparison with the modern web. > Software isn't really that bloated, it's the content. It doesn't have to be one or the other, it can be both.
MR4D 5y ago
Ouch. Something tells me that in the future on our personal computers we will be running virtual windowing systems (KDE, GTK, etc), which will make this both better and worse. That GTK (and firefox) take so much more memory to run still amazes me. If I had the time, I'd love to run an old version of Firefox on a current Linux set up just to see what would happen. --------- EDIT - I have "GTK" above, because it covers not only Gnome, but also XFCE, etc.