5.99 Performance

As a long time Eagle user who now want to switch to KiCad it seems the performance (lots of hour glasses in many places) is lagging in KiCad compared to what I’m used of for many years. Also the GUI seems a bit blurry/messy in comparison, difficult to get a “fast” workflow. I might be just not very used of it or can it be because 5.99 is a “pre 6.0” version and many things will be solved when 6.0 is out, when it will be out? So now, if interested in Kicad, is it better to go for 5.19?

I understand you are anxious for KiCad V6 to arrive and there probably is not much to add to your other thread:

What sort of response do expect about:


The light blue Icon theme is here to stay. I would have liked more contrast in the icons myself, but they’re workable and I’m slowly getting used to them. Apart from the Icons I would not know what you interpret as “blurry/messy”.

What do you mean with “difficult to get a “fast” workflow”? How much have you actually used KiCad-nightly V5.99? V5.99 has many new things and capabilities that can help you work faster, such as the selection filters in the lower right corner, making blocks and a whole lot (30+?) of other significant features. But it does take time to learn them to a sufficient level to improve your productivity. On a superficial level V5.99 is very much alike the older V5.1.x, and if you know that, then switching to V5.99 is not such a big deal and you will discover the changes gradually (Except for the blue icon theme, but that has it’s own thread :slight_smile: ).

Performance of KiCad V6 is unlikely to be much different from what KiCad-nightly V5.99 is now. It’s not as if there is some hidden KiCad version that will suddenly be revealed as KiCad V6. It will just be an incremental bugfix upon V5.99.

KiCad V5.99 is plenty quick for what I do with it, and most is about the same as KiCad V5.1.x. to me it even feels like lots of things are a bit quicker. DRC does run quite slow though, but it does many more checks and you do not have to run it often. I also have to confess that I make relatively simple PCB’s and do it on an almost 10 year old PC. If you’re designing big and 20 layer PCB’s on a fast PC a performance comparison may be different.
I also notice the interactive router “stuttering a bit” every now and then, but it also resolves issues better then in V5.1.x. so those CPU cycles appear to be doing something useful.

Whether to switch now to V5.99 or use V5.1.x depends more on your personal view and needs than on KiCad. Is it a hobby, or do you need it to buy your food and maintain the roof above your head? Are you a cautious person or adventurous? An early adopter or a trend follower?

That said. Early in the design cycle of a new KiCad version some *&^%$#@! may happen that prevents KiCad from running properly for some time (weeks, months?) Now however, it’s nearing the end of a design cycle, and most changes are bug fixes, and bugs that pop up are very likely to be small and be squashed in a day or two.

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“lots of hourglasses in many places” is not a typical experience unless you are working with very large projects and/or with a very old computer. There are no big performance issues that we know about in 5.99 and plan to fix before 6.0 (we know about some performance issues for certain edge cases that affect very large designs, but these do not impact most users). So, if you are seeing these issues, unless your computer is quite old, they are likely unknown issues that should be reported with details.

My guess would be that you have icon scaling enabled here. Be sure to set this to 100

are you using fallback or accelerated graphics?
if you are (accidently) using fallback, this can be slower and visually less sharp


Thanks, the computer I use is quite “modern”, an Intel i7 8800/fast SSD’s/ 64G RAM and a pretty decent graphics board. What I say here is I compare it with Eagle, the same kind or actually exactly the same projects. What I describe here is very much a “feeling” which in the long run disturbs the work flow/creativity which I can’t explain so much better than this. I have never really ran 5.19, so KiCad 5.99 is quite new for me.

Feeling like the workflow is slow and experiencing actual pauses / “hourglasses” are very different. Without any more details about what you mean it is hard to say whether or not there is actually a problem you are seeing, or you are just used to Eagle and are working more slowly in KiCad because you are new to the program.

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As a

it takes some time to get used to another program. Some 6 or 7+ years ago I did an evaluation of PCB programs and also tried eagle, and I found it’s interface very weird. I had a 0.2Ohm power shunt resistor that I wanted to use, and that resistor value was not in eagles drop down list for resistors.

When I evaluated KiCad I made a (simple) example PCB from start to finish with the (then) excellent “Getting started in KiCad” guide. KiCad was quite rough back then, but I liked the way it worked, the excellent schematic symbol and footprint editors and the simple ways that any schematic symbol can be mated with any footprint. The “Interactive Router” did not exist yet back then (or was hidden in that “other” canvas) and I thought the 3D viewer was a gimmick, but it later proved to be a worthy addition.

I’d think that depending on your personality you have to do between 3 and 6+ “serious” projects in KiCad to get into it’s groove and after that you can concentrate on your projects instead of learning KiCad and your productivity comes back.


Dear paulvdh, this was a good reply from you and I totally agree! We will soon see if I’m a happy KiCad user or not. Things can of course take its times…

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One area where KiCad actually is very slow is loading or reloading the libraries when something has changed so that they need reloading. Specifically the footprint libraries. Sometimes it takes a minute or so, even with a decent machine with SSD. I hate it.

Other than that, I don’t feel any slowness. KiCad is very snappy even with old hw. Some functions of course necessarily take some time so that they aren’t within 0.1 second immediate, like running the DRC or filling zones if the design is nontrivial.

As others have said, it would be easier to answer if you can identify some specific workflow or function which feels slowish.

If you want I can make a video or 2 some day to show what’s “slow” and sometimes seems a bit illogical. Its not always very easy to explain in text what “stops the flow”…


… and also (might be a bug/must be so) after converting an Eagle project to KiCad some (or many) nets have no connections/net references at all in the PCB. So, patient as i am, I try to re-route it in the schematics, re-annotate and “update pcb from schematics” to the PCB, still no connections…

It might be worth checking your video drivers.

You don’t say what OS you’re using, though with the mention of “hour glasses” I’m guessing Windows?

Some time ago there was an interaction between KiCad and certain AMD video driver features for Linux that caused shockingly poor response times. Like 1 to 2 seconds to do anything that moved the view. The fix was to turn off that particular feature in the video driver.

I wouldn’t be surprised if you’re dealing with some issue like that.

The way nets work in eagle is quite different from KiCad.
From what I understand a “net” in Eagle is a list of pin names that connect together, while in KiCad it are the (default green) wires themselves and their endpoints on the pins of schematic symbols that define a net.

During Eeschema / Tools / update PCB from Schematic [ F8 ], KiCad generates a netlist (internally) and ports it to PCBnew, but it is a manual operation. What I understand from eagle, it always tries to keep the schematic and PCB in sync continuously.

Because of this difference, the Eagle importer has to jump through some hoops to translate the netlist. I think this difference in concept may also be quite important if you have experience with Eagle and want to learn KiCad. A short overview of differences is in:

I used the importer only a few times just out of curiousity, and once for a decent sized project, and that required quite a lot of manual repair work, but it was a lot better then the alternative (re do everything). In it’s current state the eagle importer is not perfect, but it’s usable. It’s also still being actively improved. Just the last few days two changes have been made: https://gitlab.com/groups/kicad/-/issues?scope=all&state=closed&search=eagle

I’d wager a bet this is the issue the OP is having.

An NVME M.2 drive significantly reduces the loading time over a SATA SSD.

The file per item model makes this time depend a lot on the antivirus software used

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For the time being it’s OSX Catalina (10.15.7) and I don’t see graphical issues because of the hardware, it’s the programs own behaviour is certain situations and look (icons design etc/may be becaus I’m not yet used of it/normalised) which seem to be the issue; as mentioned I compare it with Eagle in similar situations. One thing in KiCad is fantastic and it’s the 3d-viewer, the look of the PCBs is probably the best/most real looking one out there, compared to any other PCB software I have seen. One thing which is kind of a mess, though, once again compared to Eagle which runs exactly like all software should run, is front/back/update this update that, click here, click there to annotate schematics/PCB to stay in “sync”…

Automatic schematic -> pcb update has been discussed some times. See https://gitlab.com/kicad/code/kicad/-/issues/4469. You can add a thumb up there to make your opinion known (it may even affect the priority list of the developers).

The annotation dialog is mostly unnecessary IMO and newly added items should be annotated automatically; see https://gitlab.com/kicad/code/kicad/-/issues/1973. The dialog popping up breaks the workflow when not summoned on purpose.

One thing I’ve (re) discovered to be noticeably slow is moving big blocks. As a test I have a schematic with 1200 resistors and moving them all in Pcbnew gives a screen update rate of about 1Hz. (But I am doing this on an old first gen i7-870).

When they are all selected zooming and panning is also noticeably slower compared with those resistor not selected / highlighted.

My experience with KiCad is that it’s quite snappy, even on low-end spec’d machine (as for today standards: 2.6GHz dualcore i5, 16GB Ram, ordinary SSD).
Except for some library loading (usually only on startup) there are no operations that cause any serious slow-downs.
Definitely, some video screencast would help to find out whether your @TheSwede experience with KiCad is normal or not (e.g. caused by some incompatibility/other issues).