Speeding up low priority stuff on a Mac

Posted in Commentary, Geekfest on December 29th, 2019 by juan

I’m in the middle of taking a MacBook Pro I have that’s been sitting idle and setting it up as my kid’s computer. First thing I had to do was to wipe it clean. Then a reload (High Sierra was loaded on it). As part of the setup, I stupidly turned on FileVault.

I then went to upgrade to Catalina and I have to wait HOURS while the drive is encrypted. That’s ridiculous. It’s a brand new install with nothing on the encrypted drive but the basic OS install.

However, I did find a neat little trick and figured I would share:

sudo sysctl debug.lowpri_throttle_enabled=0

That disables the low priority mode for a bunch of services like Time Machine and FileVault. The progress bar is still showing hours, but it’s significantly faster. In the few minutes I’ve had it on, the progress bar has moved from ~20% to ~50%!

Great tip for future reference.

Oh, and this does not persist across boots. Not sure I want it on all the time, but in case I do, there is a mechanism to do that via Launch Daemons. I’ll experiment with that on this MBP when I’m running Catalina. I fear that it will not work there because of the new sandboxing of the OS. More on that later.

One more basic diversion

Posted in Commentary, Geekfest on December 26th, 2019 by juan

I found and loaded a copy of BBCBasic on the AltairDuino. This is a basic I never used when I was really running CP/M but it looked interesting. In the veins of the previous MBASIC post, I ran the sieve on it to see how well it ran:

[2019-12-25 10:45:15] >LIST
[2019-12-25 10:45:17]     5 PRINT "Start"
[2019-12-25 10:45:17]    10 DIM flag%(8191)
[2019-12-25 10:45:17]    20 count = 0
[2019-12-25 10:45:17]    30 FOR i = 1 TO 8191
[2019-12-25 10:45:17]    40   flag%(i)=1
[2019-12-25 10:45:17]    50 NEXT i
[2019-12-25 10:45:17]    60 FOR i = 0 TO 8190
[2019-12-25 10:45:17]    70   IF flag%(i+1)=0 THEN GOTO 150
[2019-12-25 10:45:17]    80   prime = i+i+3
[2019-12-25 10:45:17]    90   k=i+prime
[2019-12-25 10:45:17]   100   IF k > 8190 THEN GOTO 140
[2019-12-25 10:45:17]   110   flag%(k+1)=0
[2019-12-25 10:45:17]   120   k=k+prime
[2019-12-25 10:45:17]   130   GOTO 100
[2019-12-25 10:45:17]   140   count = count + 1
[2019-12-25 10:45:17]   150 NEXT i
[2019-12-25 10:45:17]   160 PRINT "End, Primes =", count
[2019-12-25 10:45:17] >RUN
[2019-12-25 10:45:19] Start
[2019-12-25 10:50:49] End, Primes =             1899
[2019-12-25 10:50:49] >

As you can see, the code is slightly different. The indentations are provided natively by BBCBasic. Interesting note is that I couldn’t LOAD(yes, it all has to be caps) the code. This Basic is expecting a tokenized form. However, I did some sleuthing and found out you can *EXEC "FILENAME.TXT" and it will import an ASCII file in.

Anyways, the result above is pretty clear. This basic runs the sieve in 5 minutes 30 seconds or roughly 21% faster. Cool. Wish I’d know about this back in the day.

And an Altair diversion

Posted in Commentary, Geekfest on December 24th, 2019 by juan

Back to the future with an Altair!

Retro computing is one of those things that I dabble in. I’d like to do it more, but there’s this thing with time that I don’t have a lot of. But during one of my breaks this last year, I was able to put together one of the AltairDuino Altair replica kits. It’s cool because of all the effort that went into building it and the fact, that I have a dedicated Altair sitting next to me on my desk. One of the semi-recent updates to the emulation code allowed me to run Z80 CP/M (as opposed to the real 8080 stuff). Lots of fun code can be run this way including Turbo Pascal and such.

But – I wanted to know how fast this was. The canonical test of the time was/is the Sieve in basic.

I took the code I had laying around from my experiments with my Atari 800 and modified it to run in the more limited space of the simulated CP/M environment. The change was to put a % next to the flags variable. In MBASIC that marks it as an 8 bit integer. Without that, the program runs out of space. Here’s the code:

10 DIM FLAG%(8191)
20 COUNT = 0
30 FOR I = 1 TO 8191
40 FLAG%(I)=1
60 FOR I = 0 TO 8190
70 IF FLAG%(I+1)=0 THEN GOTO 150
80 PRIME = I+I+3
100 IF K > 8190 THEN GOTO 140
110 FLAG%(K+1)=0
130 GOTO 100
140 COUNT = COUNT + 1
150 NEXT I

And here’s the time stamped output of the run:

[2019-12-24 13:59:10] run
[2019-12-24 14:06:09]  1899
[2019-12-24 14:06:09] Ok

How’d I get the timestamps you ask? Well a bit of background on that. The Altair didn’t come with a "console". You used a serial port to connect it to some sort of terminal. What I’ve done is used a USB to serial cable that connects my iMac to the Altair. I then used minicom which I install via homebrew. One of the options of minicom is to timestamp all the output lines in the serial connection.

Anyways. My little emulation thing ran the sieve in just under 7 minutes. Comparable to a time appropriate machine. Cool.

and the lab is up

Posted in Geekfest on August 13th, 2016 by juan

Ok so I got it working on Sunday, but I’ve had a long week and didn’t have a chance to update. The C6100 is up and running. I’ve moved it into the DCF and surprisingly, the noise on it is actually so little, I can not hear it through the door. That was one of my biggest concerns. Long story short, the process was involved, but mostly because the SSL certs on the management IPs are so outdated.

So all that said, this is what I ended up with:

I’ve never had that much compute, memory, storage, or anything. That was a very, very large data center not long ago.

Cool. Now on to other cool stuff.

Oh… and a couple of things to note in case someone is actually reading this.

The back of the C6100 gets **hot**. I noticed in the move from my office into DCF that the USB thumb drives I’m using for boot were very hot. I’m concerned that it’s going to take them beyond supported limits, so I bought a set of little pig tails to have them off the motherboard.

Also – this thing runs relatively low power, but it is sucking about 660 watts being mostly idle. I’m going to have to buy another power supply and another UPS to make sure that I survive more than 5 minutes of outage.

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update on the DCF upgrade

Posted in Geekfest on August 7th, 2016 by juan

Got the C6100 on Friday (8/5). The system is as described by the seller on eBay, but … FFS … it only included one power supply! Tried getting the thing going and ran into immediate snags. First, each node only has two USB ports. My intent is to boot this guy off of USB, but I need a keyboard, and a USB key to do the install and a USB drive to use for boot. One too many. So I tried using a hub to attach the key and the keyboard. Couldn’t get it to boot. Moved the key to a dedicated port and had the USB “drive” on the hub with the intent to move the “drive” to a dedicated port once the install was complete.

No Go.

So, next step was to try to use the remote management to mount a virtual CD. I tried connecting with a current release of Chrome from my production iMac. Well, wouldn’t you know it – you need Java to do that. Don’t want to install that on my main iMac, but I was going to do that for the sake of the project. But before I did that, I wanted to see if Firefox would run it better. Firefox won’t connect to the port because of a security warning on the old HTTPS certs on the box. Same thing with Safari. That made me fire up a Windows 8.1 VM. Same issues. And, oh, during all of that my internet connection goes out … for 3 hours. AHHHH. Well undeterred, I find an old XP VM. That too didn’t have Java loaded.

End of Line.

Back to the project now (Sunday 8/7/16).

First thing first, though, I have to finish the PFsense build and roll out. Cross your fingers. Lots of work.

Sophia! Please give me 100 licenses for internal use. I promise it’s not commercial work! Also note that I’ve single handedly driven multiple deals for you because I brag about your stuff to just about all the customers I visit. And I visit lots of customers. Lots and lots.

Another fresh start

Posted in Geekfest on August 7th, 2016 by juan

So, like usual, I’m sitting on a plane and have little to do. Figured that this is a good time to start writing for my blog again. It’s been much ignored recently, but a new update to Ulysses just came out and it supports posting directly to WordPress sites.

There’s been much that has changed since I last posted. Much has changed in my personal life, but much has also changed in my nerdery. My home network now has over 45(!) things with IP addresses on them. This is forcing me to make a change that I did not want to do. For years I’ve been running the Home Edition of Sophos UTM. I really couldn’t be any more pleased with the functionality of it, but for whatever reason, it is limited to only 50 internal IPs. Now, granted, when I first got the software, that seemed like a ridiculous number. But, as with all such things (640K of RAM – who’ll ever use that much?), the time has come for me to move on. My first attempt was to use the next generation firewall from Sophos. Well that failed 30 minutes into me trying to use it. Many of my devices have static IP addresses handed out to them via the DHCP server. When I was taking those address into the new firewall, it TIMED OUT ON ME AFTER I PUT THEM ALL IN. Yup 30 minutes of laboriously entering MAC addresses, IP addresses, and host names – the damned thing failed. You see, Sophos didn’t develop a migration tool from the old UTM to the new “goodness”. Time to move on.

So – this weekend, I’m going to pfsense. It’s not as slick. It doesn’t do all the UTM stuff. It’s clearly written by folks that are nerds like me and not professional UI dudes (no disrespect intended). I’m going to miss some of the features of Sophos, but I have to move on.

Why you ask? Well – that’s the good part of this story. I just bought a new (well to me), Dell C6100 four node blade system for my home lab. It’s going to bring 32 cores, 192GB of RAM, and lots of other things to the home DCF (Data Control Facility for you new readers). That gives me enough juice to run most of the “hard core” stuff my vendors are trying to shove into Datalink. It’ll be fun having a really nice home cluster again.

But … to get that guy on my network, I’m going to have to doll out at least 12 more IPs just for the hardware. Imagine home many more I’m going to have to hand out once I start firing that guy up full of VMs.

Yeah – I’m a nerd and have first world problems – but that’s how I learn and make a living.

More to come…


Old computers were fast (back then)

Posted in Geekfest, Musings on April 9th, 2012 by juan


I have many vices. One of them is collecting old computers. To me, those are the 8 bit systems that were popular in the late 70’s and early 80’s. This last week, I was able to get a nice collection of Atari 800 and 400 machines from a local craigslist entry. Those are fun machines and bring me back to learning programming for the first time. My first computers was a TRS–80 Model 1, Level 1. However, the first machine I had access to that had “real graphics” was an Atari 800 in the computer lab at my middle school. I loved playing with the graphics and remember learning all sorts of tricks to make it faster.

I got to playing with the Atari’s and typed in some Basic programs just to see the thing do its thing. I remember them being fast back in the day. Well here I am 30 some odd years later with a computer that would seem as something out of a far future world to my little self then (4 processors! 4GB of RAM! 256GB of Solid State Disk! Wireless networking to the world at 50Mbit! Megapixel display with 32bits of color depth/pixel! On my lap! At it weighs less than 2 1/2 LBS! Seriously? That’s can’t possibly be! Oh – and that’s just my laptop. Don’t forget I have a “real” computer too.) Those ATARI’s were not fast.

Being the geek that I am, I had to see how much faster we have it today. I poked around the net for a bit and found an implementation of the Sieve of Eratosthenes on this site. I entered it into my Atari and it did come in at just around 5 1/2 minutes. I had to test it against my current computers, so I downloaded a copy of Chipmunk Basic. It seemed like a fair test to compare an interpreted basic to an interpreted basic. Here’s the basic version I wrote up:

10 dim flag(8191)
15 for a = 1 to 1000
20 count = 0
30 for i = 1 to 8191
40 flag(i)=1
50 next i
60 for i = 0 to 8190
70 if flag(i+1)=0 then goto 150
80 prime = i+i+3
90 k=i+prime
100 if k > 8190 then goto 140
110 flag(k+1)=0
120 k=k+prime
130 goto 100
140 count = count + 1
150 next i
160 rem print count
170 next a
180 print a;"iterations"

The big difference between my version and the ATARI version is that I had to run my version for 1000 iterations for me to get meaningful timings. The results?

[juan:~]$ time basic t.b
1001 iterations
basic t.b  7.63s user 0.00s system 99% cpu 7.639 total

That works out to be that my laptop is about 43,000 times faster than that ATARI. On one core. Let’s see what it’s like on all cores:

[juan:~]$ for i in {1..4}
for> do
for> time basic t.b &
for> done
[2] 30012
[3] 30013
[4] 30015
[5] 30017
[juan:~]$ 1001 iterations
basic t.b  18.80s user 0.03s system 98% cpu 19.029 total
[2]    done       time basic t.b
[juan:~]$ 1001 iterations
basic t.b  18.76s user 0.03s system 98% cpu 19.069 total
[3]    done       time basic t.b
[juan:~]$ 1001 iterations
basic t.b  18.80s user 0.02s system 98% cpu 19.069 total
[5]  + done       time basic t.b
[juan:~]$ 1001 iterations
basic t.b  18.79s user 0.03s system 98% cpu 19.097 total
[4]  + done       time basic t.b

Or roughly 70,000 times faster.

But wait. That site that had the listing for the Basic version also had one for one in Action! (which was a compiled language for ATARI’s). That version ran in about 1.5 seconds according to the Analog article ( I don’t have the Action! package to verify). Well I couldn’t not measure that too. So I wrote a C version of the Sieve. It’s a very dumb version intended to match the basic one as closely as possible:

#include <stdio.h>

int sieve()
  int flag[8192];
  int i,count,k,prime;

  for(i=0;i<8192;i++) {


  for(i=0;i<8190;i++) {
    if (flag[i]) {
      while(k<=8190) {

  return count;

int main()
  int c,i;

  for (i=0;i<=100000;i++)

  printf("found %d, %d times\n",c,i-1);

It turns out that this compiled version is so fast that I had to run is 100,000 times to get measurable results:

[juan:~]$ gcc -O4 t.c -o t
[juan:~]$ time ./t
found 1899, 100000 times
./t  4.17s user 0.00s system 99% cpu 4.177 total

And to do it on all the cores:

[juan:~]$ for i in {1..4}
time ./t &
[2] 30449
[3] 30451
[4] 30452
[5] 30454
[juan:~]$ found 1899, 100000 times
./t  7.44s user 0.01s system 95% cpu 7.832 total
[5]  + exit 25    time ./t
[juan:~]$ found 1899, 100000 times
./t  7.51s user 0.01s system 95% cpu 7.850 total
[3]  - exit 25    time ./t
[juan:~]$ found 1899, 100000 times
./t  7.46s user 0.01s system 94% cpu 7.891 total
[2]  - exit 25    time ./t
[juan:~]$ found 1899, 100000 times
./t  7.49s user 0.01s system 94% cpu 7.897 total
[4]  + exit 25    time ./t

Or roughly about 80,000 times faster.

All that on my laptop while I’m sitting in bed. Running on batteries.

The future is cool.

On Lion and recovery

Posted in Fanboy, Geekfest on September 20th, 2011 by juan

I’m 30K feet plus up in the air right now. Doing some work with my MBA. Can’t tell you again how cool it is to be able to work while I’m sitting on a plane. With a real computer.

So – I’m typing away at a blog post for work. As usual, I have my retinue of open apps doing their thing: chrome (I’ll talk about this vs safari some other time), iterm2 (you know about that right?), mail, and preview. I’m switching between preview and marsedit to write the blog post and all of a sudden my keyboard doesn’t respond. Even worse, I can’t command-tab to switch to another app to see if I can fix it. Switching over to iterm2 doesn’t let me type on the command line (which has always been my failsafe way of fixing things). I even try the shut the lid, go to sleep, and wake trick. That usually fixes keyboardy things. Nothing. I start panicking a little. I’ve been working on the work blog for a while and have much mental sausage already spent on it. In desperation, I close the lid, open and try to switch to another user (you do have another user just in case right?). That doesn’t work either. Can’t type in the login window!

The only thing that works is the shutdown button in the wake from sleep screen. I hit it and I’m asked for a login again. OH NO! But luckily, I can type in my admin user and password, at which point my MBA reboots. Because of the cool SSD thing, the reboot is very quick. With trepidation I login to my regular user and …

and …

It’s all back! All of it. My apps are where they are normally hidden (spaces), and Marsedit has my blog post open and current to the very last character I typed. Chrome recognized that I killed it and all my open tabs are brought back. Mail is happily doing it’s thing. iTerm2 is there waiting, flashing the cursor, beginning me to vi or something.

I’ve never had a full panic shutdown restart experience not cost me any work. Never. Lion fixed that. Somehow. Magic.

Now the question -what happened? Why did I lock up? I have a suspect. The only thing that didn’t come back is preview. It complained that the file I was looking at was not available because I didn’t have permissions to it. Hmmm… That file was in my dropbox and was just recently upgraded to one of the beta releases. I’m pointing the finger at that.

so I remember

Posted in Commentary, Geekfest, Musings on March 10th, 2011 by juan

One of my clear recollections of my early computer usage was the day that I bought my first hard drive. At 5 MEGA BYTES it seemed a luxury beyond all imagining. It only cost me $3,000.00. In 1980.

Had the same feeling in the mid 80’s when I upgraded my Amiga to 2MB of RAM (remember the sidekick?) and a 40 MB hard drive. It seemed like RAM beyond measure. Storage beyond possible utilization.

In the early 90’s my work gave me a computer with a super high rez screen, UNIX, 4 MB of RAM, and 1GB of hard disk, and a SPARC Based UNIX operating system with INTERNETS. Mere PC’s were useless to me. Imagine the _power_ of my configuration.

In the early 2000’s (naught’s?), my laptop came with dozens and dozens of GB’s of hard disk space, and a Gigabyte of RAM. It used windows, but that’s before OSX became stable.

By the mid 2000’s my laptop had a 17″ screen with super high rez screen, 120 GB’s of hard disk, 1.5 GB of RAM, and UNIXes. Welcome to the vortex of Steve. The power was mind boggling.

In the mid 2010’s my laptop still had a 17″ screen, but hi-rez to a new level, 8GB of RAM, and 500GB of HD. The processor had two cores each of which is nothing less than a super computer.

By the late 2010’s I got the first desktop I’ve used consistently since the early 90’s UNIX workstations. It has a 27″ inch screen, 8 cores of super duper computer horsepower, more RAM than I have used yet (no swap), it’s connected to 20+ TB of storage in my home gigabit network. My DCF has officially exceeded a [LOC](http://libraryofcongress.gov).

My current laptop has 128GB of storage, 4GB of RAM, and two cores.

Say what?

What just happened? When did it become a feature for less to be more?

Simple: we have too much juice. All around. What we __can get__ and what we __use__ are worlds apart now.


Tags: , , ,

faster, must do faster

Posted in Commentary, Geekfest on March 6th, 2011 by juan

## Act without doing

One of the big pleasured I found since switching to the mac is [Quicksilver](http://blacktree.com). For years it was _the_ way for me to launch, open, do anything. If you’ve never used it, it’s definitely worth you looking at. Unfortunately, the developer Alcor, has moved on to a lucrative job at google and left it’s future to the tubes. When leopard came out, QS broke (supposedly – it’s fixed, but I’m fickle). That sucked for me. I’ve been looking for a replacement since. There’s a ton of products that kind of do the same thing: [launchbar](http://www.obdev.at), Google’s [quicksearchbox](http://google.com/quicksearchbox), and [butler](http://manytricks.com/butler/). But – I’ve just started using [alfred](http://www.alfredapp.com/). I like it because it’s FAST, lightweight (for me with full indexing of everything, it only consumes 12.5MB of real RAM), and it has a clipboard manager (when you buy the powerpack).

The developer is very active on twitter and on their support forums. For $15 bucks (was on special at [AppSumo](http://appsumo.com)). It’s well worth the bucks.

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