While duplicating multiple objects with Alt I’m seeing massive lag before the objects copy; sometimes upwards of 2 or 3 minutes. This is with no more then 40 (usually about half that) objects with no more then 4000 polys each. I know that is a bit to copy, but multiple minutes seems excessive. In some cases I’m even seeing lag like this with as few as 5 objects. It seems to get much worse with more objects in the level.
I would love to know if this is a known issue or if I should just avoid copying so many objects at once.
I’m using source version of UE4 running on
GTX 780ti
I7-4930k
16GB Ram
Windows 8.1
I do not believe this issue is a issue with the engine but rather just a bottleneck in creating new copies and naming those objects within the engine. RAM would probably be a big factor in this situation as I am running a system similar to yours except with WIndows 7 and 32gb of ram.
My Home system is closer to yours in regards to OS, CPU, and RAM. Anytime I’ve copied a bunch of assets I notice a hitch like this.
Testing this a few moments ago, I took the sphere asset included in starter kit and set up 5 rows of 10 (total of 50) and then copied those and with each row I copied I would select the the previous rows with it. When I got up to around copying 300 or two at a time it would stall and take a minute or so to copy.
If this is only happening in one project and not any others this may be worth investigating further.
Thanks for the quick response. I started a new level and duplicated a group of five static meshes. With each doubling the duplicate function becomes slower and slower. Finally with 960 actors selected I tried to duplicate the bunch. The cpu for UE4 is nearly frozen at 9% but it is still moving and the memory footprint is 894MB with minor adjustments up and down - though the status of UE4 is being reported as, Not responding.
Doesn’t feel like a memory issue as when I Light Build, UE4 is eating 2.6GB and Light Mass consumes between 11 and 12GB taking my pc to its max.
It has now been more than 5 minutes that UE4 has been attempting to duplicate the meshes. BTW, to clarify I’m using the 4.2 build, not the current source from Github.
One of our developers offered some insight into why the lag may be happening.
My first suspicion would be the format
we use for duplication. We export to
a text format and then parse that text
to create the new actors. If you got
some combination of a lot of actors or
extremely complicated actors the
string operations could become
noticeably expensive and possibly even
devolve in to something that gets
expensive in a non-linear fashion.
Most likely it is CPU, there is a
slight chance that it could be RAM if
the text buffer managed to get huge
enough that we started swapping, but
that seems highly unlikely given he is
saying he has 16 GB of RAM .
He also suggested that if you were using Blueprint Actors that this could result in an issue as well, but I’m not sure if you were using BP actors in your scene to copy. It is good information non-the-less.
Another potential culprit is if these
are blueprint actors. In that case,
as you’re dragging them along each one
will be having its construction script
rerun as you drag along. If there is
any significantly complicated
behaviors in the construction script,
or using a whole lot of child
actor components each spawning a new
actor as we drag along, it could also
use up CPU in a hurry.
Perhaps this will provide a little clarity on the subject. If you have any other questions feel free to let me know!
Thanks for the update. This does clear it up a little for me. It wasn’t blueprint actors I was copying, just large groups of static meshes. I was blocking out a city, so a lot of copying and pasting groups of stand-in houses. Seems to me I should jut avoid copying large groups of meshes then.
