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A comment on MacOS Catalina: Slow by Design?. Parent comment

Re:MacOS Catalina: Slow by Design? by varenc on Friday May 22, 2020 @07:25PM (#23278258)
Here's some shell script to use a random file name and have friendlier output.

  RAND_FILE="/tmp/test-$RANDOM.sh";
  time_helper() { /usr/bin/time $RAND_FILE 2>&1 | tail -1 | awk '{print $1}'; }  # this just returns the real run time
  echo $'#!/bin/sh\necho Hello' $RANDOM > $RAND_FILE && chmod a+x  $RAND_FILE;
  echo "Testing $RAND_FILE";
  echo "execution time #1: $(time_helper) seconds";
  echo "execution time #2: $(time_helper) seconds";
Introducing a network delay makes the effect much more obvious. Normally I see a delay of about 0.1 seconds, but after using the XCode network link conditioner (pf rules) to add 500ms latency to everything the delay shoots way up to ~2 seconds.

example output:

  Testing /tmp/test-24411.sh
  execution time #1: 2.32 seconds
  execution time #2: 0.00 seconds
with developer tools checked both executions report "0.0 seconds".
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Re:MacOS Catalina: Slow by Design? by varenc on Saturday May 23, 2020 @04:24AM (#23281106)
I tried just blocking "api.apple-cloudkit.com" with /etc/hosts. This reduces the delay but doesn't eliminate it. A connection attempt is still made every time. (I don't recommend making this change permanent. Just give your terminal app the "Developers Tools" permission instead)

After blocking that domain I can see that tccd and syspolicyd are logging some error messages to the console related to the failed connection. I don't recommend blocking because my guess is that'll put syspolicyd/tccd in some unexpected state and they'll repeatedly keep trying to make requests.

Try this for watching security related console log messages:

  sudo log stream --debug --info --predicate "processImagePath contains 'tccd' OR processImagePath contains 'syspolicyd' OR processImagePath Contains[c] 'taskgated' OR processImagePath contains 'trustd' OR eventMessage Contains[c] 'malware' OR senderImagePath Contains[c] 'security' "
syspolicyd explicitly logs when it makes the network request.

   syspolicyd: cloudkit record fetch: https://api.apple-cloudkit.com/database/1/com.apple.gk.ticket-delivery/production/public/records/lookup, 2/2/23de35......
(you need to enable private logging to see that url)
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Re:MacOS Catalina: Slow by Design? by saagarjha on Saturday May 23, 2020 @05:10AM (#23281380)
Enabling private logging is fairly annoying these days, unfortunately. (Interestingly, if macOS thinks you're AppleInternal, it will make it just as annoying to disable private logging…)
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Re:MacOS Catalina: Slow by Design? by varenc on Saturday May 23, 2020 @05:55AM (#23281632)
wait a sec...I recognize that name. I only know how to enable private logging thanks to your detailed and informative blog post! Seriously, it's one of the favorite macOS things I've read in a while. I loved the step by step walk through using gdb you showed.

Though just today I saw that apparently an enterprise policy config can enable private logging in 10.15.3+ without having to disable SIP. https://georgegarside.com/blog/macos/sierra-console-private/

For reference for others: this is the blog post by OP on enabling private logging in Catalina. check it out! https://saagarjha.com/blog/2019/09/29/making-os-log-public-o...

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Re:MacOS Catalina: Slow by Design? by saagarjha on Sunday May 24, 2020 @03:58AM (#23289953)
I’m glad you appreciated it, but I think it also happened to be some of the fastest-to-deteriorate advice I’ve given :) I should go back and revisit this, as on my system I have it currently stuck in a state where it unconditionally enables private data logging at boot (which mean my crash logs have personal information in them unless I remember to turn it off with the workaround I’ve been using until now…)
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Re:MacOS Catalina: Slow by Design? by krferriter on Saturday May 23, 2020 @12:29AM (#23279897)
Huh this is crazy. 2 seconds is way slow and this shouldn't involve any network activity. Seems like a real problem.
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Re:MacOS Catalina: Slow by Design? by Erlich_Bachman on Saturday May 23, 2020 @04:06AM (#23280989)
He/she added an artificial network latency/delay into the config, just like they describe. That is the reason for the delay. It is made artificially long on purpose.
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Re:MacOS Catalina: Slow by Design? by maremp on Saturday May 23, 2020 @05:17AM (#23281442)
It’s not an unreasonable delay on a slow 3g hotspot. It’s problematic to have the performance tied to the network speed and suffer an overall slow performance because your network happens to be slow.
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Re:MacOS Catalina: Slow by Design? by Erlich_Bachman on Saturday May 23, 2020 @08:26AM (#23282369)
Have I written anything that is contradicts that? I simply pointed out that in the example the delay was artificial, and it was definitely due to network, not due to something other than network, as the comment suggested.
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