Calculator in Spolight causes high CPU usage mds_stores - Catalina

I have the same issue and it's frankly ridiculous. The CPU can do these kinds of quick calculations billions of times per second. Like OP, the actual calculator app doesn't show the same insane performance but there's no reason I should need another app open in order to divide two numbers. I have also experimented with reindexing Spotlight and resetting SMC, neither of which do anything.

This also has nothing to do with the fan controllers, vents, or SMC, as the community specialist above suggested. The fans are correctly responding to the fact that Spotlight inexplicably consumes all available cores and spikes the system temperature to do simple arithmetic. Something is clearly broken with Spotlight and to suggest otherwise is a laughable dodge.

Update after additional attempts to figure out this problem: Spotlight is definitely broken in some way and probably in multiple ways.

I tried limiting the Spotlight search results to *only* Calculator in System Preferences -> Spotlight -> Search Results, unchecking all options except for Calculator. In this case Spotlight fails to give any results even if I put some trivial calculation in the spotlight window. If I give it some other input (a file name, for example), it correctly states "no results", which makes sense because I turned off everything except calculator, but it also gives nothing when I give it some calculation to do. Clearly Spotlight is not correctly parsing and utilizing the categories you tell it to in system preferences. This is probably an unrelated bug to the OP's and my original problem of high CPU usage.

I then tried adding one other additional category for Search Results (applications, or documents, or spreadsheets, etc). This gave even stranger results, with Spotlight sometimes doing the calculation and sometimes not. If it did do the calculation, the CPU usage spiked like it did before. I didn't debug this extensively, but it seemed to depend on whether the other category was before or after Calculator in the list of possible Search Results. I only got it to reliably use the calculator from within spotlight if I had many categories checked.

So my best guess as to what's happening here is that spotlight is trying and completely failing to take our input (some simple math problem) and send it to the right destination (calculator app) to get the answer and return it. Perhaps it first searches all file names and contents for the string of the calculation before falling back to the calculator app if that doesn't return anything, in which case maybe it's a matter of rejiggering the priorities for what things Spotlight searches in what order.

This is a really frustrating experience. Judging from the energy usage in activity monitor, Spotlight has typically been responsible for ~20% of the total power consumption of the system when I'm on battery on my 16" MBP. This is just completely insane given how intermittently it's used and how trivial the computations are that I'm asking it to do.

This is correct. Spotlight needs to get looked at. "Community specialists" need to stop wasting users' time by suggesting SMC resets. Wish I could contribute a work around, because I love using Spotlight for quick maths.

Hello Truckster, 

Thanks for reaching out to the Apple Support Communities! I understand you have noticed the fans running higher than expected when you're using Spotlight, specifically the Calculator from Spotlight. 

You did a great job reindexing Spotlight as a first step. Next, check out the additional information under, "About fan noise," and, "Make sure the vents on your Apple product aren't blocked," from this article: About fans and fan noise in your Apple product. 

If you find that it's still occurring you may need to reset the System Management Controller (SMC) on your Mac. Resetting the SMC will not change any of the data on your Mac. The SMC works with different systems on your Mac including power, status lights, and the fans, to name a few. This article will walk you through the steps you'll follow to reset the SMC: How to reset the SMC of your Mac. 

All the best!

Exactly the same problem here. I had it before I upgraded to Catalina from High Sierra already, so it might be related to something in the user's particular configuration. Anyway it's ridiculous that the CPU usage sometimes reaches over 1000%! I reported it to Apple, no reply yet.

I have a workaround.

When mds_stores goes nuts after you enter a calculation into Spotlight, force quitting mds_stores doesn't help. But if you force quit and then immediately use Spotlight to launch an application it stops consuming CPU.

Definitely a Catalina bug. I don't remember it happening before upgrading. It seems like spotlight tries to search for the calculation in the index instead of directing it only to the calculator.

Apple has to look at it. It really impacts the Mac OS experience.

I use Spotlight often for quick arithmetic and have the same problem. Had it on an ancient 2013 MacBook Pro 15" and still have it on a brand new 16".

An annoying work around: after typing in a calculation I quickly select all and delete the string -- this prevents Spotlight from going crazy a minute later. It is ridiculous that I have to do that. And if I hear the fans start up, it's because I forgot and quickly cmd-space, cmd-a, delete, and the fans die down.

Count me in: I have exactly the same problem here. Any calculation that is active in the Spotlight pane will use all threads at max capacity (up to 1600% on 8-core MacBook Pro 16"). (As suggested above, a workaround is to erase the calculation as soon as your done with it, but it is sometimes useful to keep it there for future use/modification.)

Another problem that may be related: any search for a phone number (10 digits) crashes Spotlight instantly.

The 2 issus give the same results even when unchecking all search options in System Preferences -> Spotlight -> Search Results.

Those issues are completely new to me since Catalina.

I think I finally fixed it.

I upgraded my 16” to Big Sur yesterday to see if it was resolved but the problem persisted. I decided to see what would happen if I disabled calculator in System Preferences > Spotlight. So I toggled it off and watched Activity Monitor as I ran some simple calculations that it ignored and my CPU remained idle.

Then I toggled the calculator service back on and it now seems to behave itself. 🤷‍♂️

I’ve the same issue on my office iMac which I’ll try to update during the week if I get in. (Frustratingly Catalina broke its Thunderbolt ports so I’m not looking forward to what Big Sur will do to it)

Definitely broken in Catalina and still unfixed… Big Sur seems to have fixed the issue, but Big Sur brings quite a few compatibility issues like blocking obsolete kernel extensions (SteamInput for example).

Sad that we're being ignored... I never had this issue on Mojave and started having it when I migrated from Mojave to Catalina 10.15.4, the problem persisted after updating to 10.15.6. I thought it was a faulty update, so I tried to do a fresh install of 10.15.7 (my current version), but the problem persists.

By the way, it's not as evident, but currency conversions are also slow. For instance if you type "15EUR in USD" or anything else related, it also makes the CPU give a run for its money...

I just took delivery of a new MBPro(i7, Catalina) before Christmas and also suffer this problem. I use Spotlight for calcualtions all the time and the CPU spikes to 800% for 10-15 seconds at a time!

Crazy that this wasn't fixed on all the Catalina updates.

I don't want to upgrade to BigSur because I need other functionality of Catalina.

Are there any mds_store prefs we can zap to cure this?

Just to add that I have exactly the same issue. Calculations in Spotlight cause the CPU to go absolutely nuts. I had this problem before Catalina.