Child Item

Excessive RAM usage while syncing large files

MikeB1971

Hi Folks,

I typically sync pretty large files (image backups) and these can be as much as 250 GB+ in size.

While syncing, I notice that Dropbox reserves a seriously huge amount of memory, like the mapped file usage for my uploading file of 280 GB is currently 16 GB (not a typo).

Can Dropbox maybe give feedback on this?

For me as a layperson, an upload is essentially much like an FTP copy (I do these all the time with files this big on the internal network here) and I really don't see why this should take so much RAM. The actual app is using around 600 MB, which is perfectly fine.

Thanks,

Mike

Find more posts tagged with

Desktop

Sync

Insightful

Closed - Partially Delivered

Accepted answers

codex174

large file syncing in dropbox often shows high ram usage because of how blocks are mapped and checksummed before upload it’s not the same as a straight ftp copy since dropbox breaks files into chunks for deduplication and recovery if the mapping isn’t optimized it can create a memory bottleneck during sync the actual app footprint stays small but the process of chunking big files can eat ram fast limiting other tasks

All comments

Megan

Hey there, @MikeB1971, I hope you're doing well!

Let's see what we can do about that. As a first step, can you clarify the OS you're using, along with the app's version, and syncing status?

We need to ensure you're using a stable version, and a supported OS, and then proceed with the next steps.

Keep me posted, and we'll take it from there!

MikeB1971

Hi Megan,

Many thanks for the super-speedy reply!

Sure thing.

I'm on Windows 11, app version 186.4.6207 and my sync status is paused, more on that in sec.

About the sync status: I found that when I have syncing paused, memory usage drops to normal. At the moment it's about 40%, which is typical during a working day. But when syncing was on earlier, it rose to 90% or so. As said before, it is specifically the file being uploaded that causes this memory jump. If I use RAMMap, I can see that the Mapped File memory usage goes way up to something like 16 GB.

Perhaps this is just how things are on Windows or whatever, but it would be good to know that. I would then just leave syncing off during the day for (very) large files.

Thanks,

Mike

Megan

Hi @MikeB1971, no problem at all!

Would you mind sharing some screenshots with us too, in order for us to have visual?

codex174

ethancarter199825

thanks this explanation helps me understand why large file syncing can hit a memory bottleneck

masonbrooks074

thanks now i see how dropbox chunking big files can cause a ram bottleneck during sync

MikeB1971

Thanks @codex174 ! I've also delved into things a bit with RAM usage and it's as you say. Also the swap file usage is high while uploading, too.