Error reading file from S3 bucket with "Transport endpoint is not connected"

[jmccl]

This is entered at the request of vladem in #630.

Mountpoint for Amazon S3 version

1.10.0

AWS Region

us-east-1

Describe the running environment

Running Debian bookworm on a t2.nano ec2 instance in us-east-1. No docker / other container involved.

Mountpoint options

mount-s3 --debug --log-directory <directory> --read-only <bucket> <directory>

(Normally it runs without the '--debug' and '--log-directory' but in #630 I was asked to run with these options. The error happens in either case.)

What happened?

$ cp <file in s3 mount point> <directory>
cp: error reading '<filename>': Transport endpoint is not connected
cp: failed to close '<filename>': Transport endpoint is not connected
$ sudo dmesg -T | egrep -i 'Out of memory'
[Mon Oct 28 20:46:38 2024] Out of memory: Killed process 3470 (mount-s3) total-vm:925588kB, anon-rss:282932kB, file-rss:0kB, shmem-rss:0kB, UID:33 pgtables:752kB oom_score_adj:0

When normal processes are running (including mountpoint-s3) this is the state of ram.

$ free
               total        used        free      shared  buff/cache   available
Mem:          465116      167108      209720        2040      102356      298008
Swap:              0           0           0

Relevant log output

I'll attach a file because it's large.

[jmccl]

Log output attached.
mountpoint-s3-2024-10-28T20-44-13Z.aQxxIO.log

[vladem]

Hey! Thanks for opening this issue. I can see that you're using t2.nano instance, which has 512MiB of RAM. This explains the OOM as currently Mountpoint enforces the minimum memory target of 512MiB which allows MP to consume the entire RAM.

We'll continue looking into it and will provide updates here when we'll have them.