On 2023-07-25 15:02, Masaru Nomiya wrote:
Hello,
In the Message;
Subject : Re: Corrupted root Message-ID : <e3913bff-1048-6e9d-7b00-deb8252c158b@telefonica.net> Date & Time: Tue, 25 Jul 2023 12:41:34 +0200
[CER] == "Carlos E. R." <robin.listas@telefonica.net> has written:
CER> On 2023-07-25 11:24, Dave Howorth wrote: CER> > On Tue, 25 Jul 2023 09:11:14 +0900 DH> > Masaru Nomiya <> wrote: [...] MN>>> Now I know why FF crashes.
MN>>> I thought it was because it's a notebook PC, so it doesn't have that MN>>> much memory (8GB?). I thought that was the cause of the FF crash, but MN>>> it is not that, but too small swap size.
MN>>> The swap size should be set to the memory + 2GB (probably 10GB?).
DH>> Do you have a reference to support that assertion, please? DH>> (preferably an authoritative reference :)
CER> For a laptop, yes, recommended swap, probably automatically by CER> YaST, is memory size and a bit more ;-D
CER> My own recommendation for a computer with 8 GiB of RAM with CER> heavy use of Firefox would be 12..16 GiB of SWAP in an SSD ;-)
Thanks, Carlos.
The opinion that the conventional argument about swap does not apply to SSDs because their transfer rate is much faster than that of HDDs is presented.
But this is questionable, as Carlos also implies.
I do not recommend using a "rotating rust" hard disk if swap is in actual use. For hibernation it is ok. The reason is that I observed a huge slowdown with swap on HD I don't remember on what version of openSUSE. From one version to the next speed dropped a lot. I blamed it on "fragmentation" of the memory space on swap. There was a lot of head movement, and performance is, or was terrible. The computer was barely usable. Then I put swap on SSD, and the computer became usable again (an 8 GiB computer with heavy usage of Firefox), years ago. I still use that machine on an alternate location.
That is, I am using Tumbleweed on a 4TB SDD and 96GB memory PC with 4GB swap, and when I open as many Tabs as Carl does in vivaldi, swap is consumed as I see it. So I sometimes run # swapoff -a && swapon -a.
You do not gain speed doing that, IMO.
The transfer rate has anything to do with the swap size, I wonder?
I don't think swap size has effect on transfer rate.
Anyway, as for David's question, the reference is a well-known Japanese site for Japanese Linux users, which is written based on kernel developer Chris Down's answer to the Japanese user's question, "Is swap necessary in the current PC's situation with a lot of memory?".
https://chrisdown.name/2018/01/02/in-defence-of-swap.html
Based on this, it is said that the standard swap size is the amount of installed memory(in case of < 32GB) + 2GB since kernel 4.0, and I think that YaST2 also decides the swap size according to the same idea.
Needless to say, this does not take into account hibernation, which Carlos often mentions, with considering that Carl does not use it.
Yast probably considers that a laptop should have enough swap for hibernation, as a default choice. I can't confirm, though. -- Cheers / Saludos, Carlos E. R. (from 15.4 x86_64 at Telcontar)