Input/output error when file on a shared folder is updated on the host machine

[wildfire]

Host: macOS High Sierra 10.13.1
Guest: Ubuntu 16.04.1 LTS (kernel 4.4.0)

It seems that files on my shared folders take some time (about 10 seconds or more) to update on the guest machine when they are updated on the host machine, and the guest machine throws an input/output error if the file is in the process of being updated.

The files aren't necessary big - small HTML, PHP files, mostly less than 1KB.

This wasn't an issue before and I'm unsure what caused this to start happening. I'm clueless on how to troubleshoot this further so any idea is appreciated.

[socratis]

files on my shared folders take some time (about 10 seconds or more) to update on the guest machine

Have you tried refreshing the guest manually?

This wasn't an issue before and I'm unsure what caused this to start happening.

The question is when did this start happening? Can you downgrade and pinpoint the exact version that this started happening? It would help the developers pinpoint a potential regression.

[wildfire]

Thanks for your reply, socratis.

files on my shared folders take some time (about 10 seconds or more) to update on the guest machine

Have you tried refreshing the guest manually?

Sorry, but what do you mean by refreshing the guest? I usually connect to the guest using SSH. If I do a "ls" while the file is being updated, I usually get some weird question marks shown in this screenshot:

Question marks shown when file is being updated

vbox-file_error.png (12.43 KiB) Viewed 3544 times

This wasn't an issue before and I'm unsure what caused this to start happening.

The question is when did this start happening? Can you downgrade and pinpoint the exact version that this started happening? It would help the developers pinpoint a potential regression.

Unfortunately, I don't know when this started to happen. I am attaching the VM info obtained from "VBoxManage showvminfo" (with some private info removed).

I'm not sure if this is relevant, but this virtual machine was built using Vagrant. It was working fine before though. This started to happen within a month. I haven't made any changes to the VM settings.

Today, before I opened this forum post, I've upgraded Virtualbox to 5.1.30 and the extension pack, but this problem still persists.

[socratis]

Additions version: 5.0.18_Ubuntu r106667

Not only are your Guest Additions (GAs) old, but you are running your guest with the forked Ubuntu GAs. You need to uninstall/delete/purge them from your client and install the GAs that come with your VirtualBox installation; from the menu "Devices" » "Insert Guest Additions CD image..." and then follow the prompts. For more information see ch. 4.2.2. Guest Additions for Linux in the User Manual.