Re: Safe vm.overcommit_ratio for Large Multi-Instance PostgreSQL Fleet

2025-08-06 Thread Joe Conway
On 8/6/25 17:14, Frits Hoogland wrote: As I said, do not disable swap. You don't need a huge amount, but maybe 16 GB or so would do it. Joe, please, can you state a technical reason for saying this? All you are saying is ‘don’t do this’. I’ve stated my reasons for why this doesn’t make sense,

Re: Safe vm.overcommit_ratio for Large Multi-Instance PostgreSQL Fleet

2025-08-06 Thread Frits Hoogland
> As I said, do not disable swap. You don't need a huge amount, but maybe 16 GB > or so would do it. Joe, please, can you state a technical reason for saying this? All you are saying is ‘don’t do this’. I’ve stated my reasons for why this doesn’t make sense, and you don’t give any reason. The

Re: Safe vm.overcommit_ratio for Large Multi-Instance PostgreSQL Fleet

2025-08-06 Thread Joe Conway
(Both: please trim and reply inline on these lists as I have done; Frits, please reply all not just to the list -- I never received your reply to me) On 8/6/25 11:51, Priya V wrote: *cat /proc/sys/vm/overcommit_ratio* 50 $ *cat /proc/sys/vm/swappiness* 60 *Workload*: Multi-tenant PostgreSQL

Re: Safe vm.overcommit_ratio for Large Multi-Instance PostgreSQL Fleet

2025-08-06 Thread Priya V
Hi Frits, Joe, Thank you both for you insights *Current situation:* *cat /proc/sys/vm/overcommit_memory* 0 *cat /proc/sys/vm/overcommit_ratio* 50 $ *cat /proc/sys/vm/swappiness* 60 *Workload*: Multi-tenant PostgreSQL *uname -r* 4.18.0-477.83.1.el8_8.x86_64 *free -h* total used free shared b

Re: Safe vm.overcommit_ratio for Large Multi-Instance PostgreSQL Fleet

2025-08-06 Thread Frits Hoogland
Joe, Can you name any technical reason why not having swap for a database is an actual bad idea? Memory always is limited. Swap was invented to overcome a situation where the (incidental) memory usage of paged in memory was could (regularly) get higher than physical memory would allow, and th