<story><title>FreeBSD replaces bubblesort with mergesort on SYSINTs</title><url>https://twitter.com/cperciva/status/1693127769901969772</url></story><parent_chain><item><author>srcreigh</author><text>Very OT, but I concur. I need a DSP for my car audio system. I considered a rpi3 with a DAC attachment.&lt;p&gt;I tried the raspbian OS with some moderate overclocking and removing unneeded startup processes. Couldn’t get it under 25 seconds for boot. Kind of a deal breaker (remote start unit could help, but…)&lt;p&gt;Apparently somebody can start the rpi3 in &amp;lt;3 seconds. I’ll believe it when I try their image myself. Their setup disables USB and networking (maybe audio too who knows) which is a giant pain for configuring my system.&lt;p&gt;Maybe I’ll try again with an RPi 4 and usb3 nvme. or maybe I’ll just pay hundreds of dollars for a dedicated DSP unit.&lt;p&gt;In case anyone cares, my main use case is parametric EQ for phon adjusted low bass frequencies. 90dB 20Hz sounds as loud as 70dB 50Hz (give or take) and subwoofers are generally quieter at lower frequencies. Hence, audio processing unit to cut as you go higher than your lowest decently loud frequency.&lt;p&gt;The lowest cost option for this is about $230USD plus some electrical components (miniDSP 2x4HD). I figure the rpi would cost around $100 including the DAC unit, open source audio software, just need some power source to link the battery to the rpi power cord.&lt;p&gt;Edit: I don’t want to spam thanks comments for helpful replies, so I’ll just say it here (possibly in advance): thanks!!!</text></item><item><author>atmosx</author><text>There was an article about a Linux embedded system handling a car back-camera that had to boot within 3-5 seconds or something along those lines.</text></item><item><author>timmaxw</author><text>For people (like me) who are wondering why a kernel needs to boot in under 28ms: It&amp;#x27;s for virtual machines that get launched on-demand in services like AWS Lambda. &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.daemonology.net&amp;#x2F;blog&amp;#x2F;2022-10-18-FreeBSD-Firecracker.html&quot; rel=&quot;nofollow noreferrer&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.daemonology.net&amp;#x2F;blog&amp;#x2F;2022-10-18-FreeBSD-Firecrac...&lt;/a&gt;</text></item></parent_chain><comment><author>JeffeFawkes</author><text>If you make your own buildroot image, you can get VERY quick boot times - here&amp;#x27;s a random vid I found [1] with 3.5 seconds on a pi zero w (which is considerably less powerful than a Pi3.&lt;p&gt;I&amp;#x27;ve worked with similarly underpowered boards (licheepi zero, only has 64mb ram and uses the cpu from a dashcam!) and those will still boot and start an SDL app in under five seconds.&lt;p&gt;If you can identify the bare minimum that you need for your EQ solution, you can probably get similar boot times.&lt;p&gt;[1]: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.youtube.com&amp;#x2F;watch?v=ZehLyumyMvE&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.youtube.com&amp;#x2F;watch?v=ZehLyumyMvE&lt;/a&gt;</text></comment>
<story><title>FreeBSD replaces bubblesort with mergesort on SYSINTs</title><url>https://twitter.com/cperciva/status/1693127769901969772</url></story><parent_chain><item><author>srcreigh</author><text>Very OT, but I concur. I need a DSP for my car audio system. I considered a rpi3 with a DAC attachment.&lt;p&gt;I tried the raspbian OS with some moderate overclocking and removing unneeded startup processes. Couldn’t get it under 25 seconds for boot. Kind of a deal breaker (remote start unit could help, but…)&lt;p&gt;Apparently somebody can start the rpi3 in &amp;lt;3 seconds. I’ll believe it when I try their image myself. Their setup disables USB and networking (maybe audio too who knows) which is a giant pain for configuring my system.&lt;p&gt;Maybe I’ll try again with an RPi 4 and usb3 nvme. or maybe I’ll just pay hundreds of dollars for a dedicated DSP unit.&lt;p&gt;In case anyone cares, my main use case is parametric EQ for phon adjusted low bass frequencies. 90dB 20Hz sounds as loud as 70dB 50Hz (give or take) and subwoofers are generally quieter at lower frequencies. Hence, audio processing unit to cut as you go higher than your lowest decently loud frequency.&lt;p&gt;The lowest cost option for this is about $230USD plus some electrical components (miniDSP 2x4HD). I figure the rpi would cost around $100 including the DAC unit, open source audio software, just need some power source to link the battery to the rpi power cord.&lt;p&gt;Edit: I don’t want to spam thanks comments for helpful replies, so I’ll just say it here (possibly in advance): thanks!!!</text></item><item><author>atmosx</author><text>There was an article about a Linux embedded system handling a car back-camera that had to boot within 3-5 seconds or something along those lines.</text></item><item><author>timmaxw</author><text>For people (like me) who are wondering why a kernel needs to boot in under 28ms: It&amp;#x27;s for virtual machines that get launched on-demand in services like AWS Lambda. &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.daemonology.net&amp;#x2F;blog&amp;#x2F;2022-10-18-FreeBSD-Firecracker.html&quot; rel=&quot;nofollow noreferrer&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.daemonology.net&amp;#x2F;blog&amp;#x2F;2022-10-18-FreeBSD-Firecrac...&lt;/a&gt;</text></item></parent_chain><comment><author>red0point</author><text>It doesn‘t always have to be a RPi, sometimes there is dedicated hardware for that use case that is also kinda cheap.&lt;p&gt;Check this thing out, it‘s a programmable audio DSP:&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.thomannmusic.ch&amp;#x2F;the_t.racks_dsp_4x4_mini.htm&quot; rel=&quot;nofollow noreferrer&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.thomannmusic.ch&amp;#x2F;the_t.racks_dsp_4x4_mini.htm&lt;/a&gt;</text></comment>