Instant sleep on MacBook - no sleepimage

Apple really cares about the content of my Macbook RAM. But I don't - I'd prefer to have that extra 2-3 minutes back when closing the lid.
The good news: You can customize the sleep mode on your Macbook so it does not save the content of your memory to the disk before sleeping.

When you put a Macbook into sleep, by default, it will page out your memory to the disk (/var/vm/sleepimage) - in case the battery gets depleted you still have your work saved. This is called hibernatemode 3:


 hibernatemode = 3 (binary 0011) by default on supported portables. The system will store a copy of memory to persistent storage (the disk), and will power memory during sleep. The system will wake from memory, unless a power loss forces it to restore from disk image.


The issue is that if you have a lot of memory (8-16Gb), it takes a good while to swap it out and isn't particularly useful for storing on a small SSD drive or in fact extending the life of the drive itself.

To turn it off, simply use


sudo pmset hibernatemode 0

If you want to revert it back to the default setting, use

sudo pmset hibernatemode 3


For more info on pmset, visit the man page on Apple developer site.

Comments

Post a Comment

Popular posts from this blog

MurMurHash3, an ultra fast hash algorithm for C# / .NET

Image
Finding good hash functions for larger data sets is always challenging. The well know hashes, such as MD5, SHA1, SHA256 are fairly slow with large data processing and their added extra functions (such as being cryptographic hashes) isn’t always required either. Performance and low collision rate on the other hand is very important, so many new hash functions were inverted in the past few years. One of the most notable ones is MurMurHash3, which is an improved version of its predecessor (v2). The new version can create both 32 bit and 128 bit hash values, making it suitable for a wide range of applications. 64 bit architecture The 32 bit hash isn’t too important for large amount of data matching, so I only worked with and tested the 128 bit version. The latter one is optimized for x86-64 architecture, giving amazing speeds for data processing. As a 128 bit value consists of two 64 integers, the processor is fairly good with working with such large hash values – they are not byte
. . .

Read more »

ESP32 - send a push notification from the Arduino ESP32 device to your phone

Image
Sending a push notification to your phone from an event from an ESP32 is simple. What you'll need (if you are using a Mac for development): Arduino IDE Arduino for ESP32 Serial port simulator for ESP32 to upload your code to the board Wifi network IFTTT account IFTTT app on your phone Wifi network that your ESP32 board can access Architecture Create an IFTTT applet This should read something like this: If Maker Event "notification", then Send a notification from the IFTTT app Change the notification template Go to the settings of your new IFTTT applet and change the template to include "Value1", like this: Get your Webhook endpoint in IFTTT On your applet, click the triangle looking thing (webhook), then Settings, or simply go to this URL  https://ifttt.com/maker_webhooks/settings   Visit the private URL in your browser, replace the trigger name with "notification", so it reads like ...trigger/notification/ with/... and in the Value1 field type in a
. . .

Read more »

Octoprint as a systemd service - running it with high priority

Image
Octoprint provides remote access to your 3D printer, and as it's written in Python, you can run it on practically any operating system. If you are using a standard Raspberry PI image (for instance, because you run it on an Orange PI ), rather than the customised Octoprint image, you can manually install it and create a systemd service to run it: Add this to /etc/systemd/system/octoprint.service  [Unit] Description=Octoprint After=network.target [Service] ExecStart=/home/pi/octoprint/bin/octoprint serve WorkingDirectory=/home/pi/octoprint StandardOutput=inherit StandardError=inherit Restart=always User=pi CPUSchedulingPolicy=rr CPUSchedulingPriority=80 [Install] WantedBy=multi-user.target Then run sudo systemctl daemon-reload sudo systemctl enable octoprint This will start Octoprint on every reboot with a high priority (so unlikely to stutter during printing).
. . .

Read more »