VirtualTam's bookmarks

1. HyperLogLog - Approximate the number of distinct elements in a set 2022-12-14

   tags: algorithm, database/postgresql, database/redis

   [ permalink ]

   • HyperLogLog: the analysis of a near-optimal cardinality estimation algorithm (PDF)
   • HyperLogLog in Practice: Algorithmic Engineering of a State of The Art Cardinality Estimation Algorithm
   • https://agkn.wordpress.com/2012/10/25/sketch-of-the-day-hyperloglog-cornerstone-of-a-big-data-infrastructure/
   • Redis new data structure: the HyperLogLog
   • https://www.reddit.com/r/programming/comments/21wshj/redis_new_data_structure_the_hyperloglog/
   • https://redis.uptrace.dev/guide/go-redis-hll.html
   • https://towardsdatascience.com/hyperloglog-a-simple-but-powerful-algorithm-for-data-scientists-aed50fe47869
   • https://odino.org/my-favorite-data-structure-hyperloglog/
   • http://blog.notdot.net/2012/09/Dam-Cool-Algorithms-Cardinality-Estimation
   • https://supabase.com/blog/seen-by-in-postgresql
   • https://www.citusdata.com/blog/2017/12/22/distributed-count-vs-hyperloglog/
2. 0.30000000000000004 2019-09-09

   tags: approximation, arithmetic, float, hardware/ram, memory, programming

   [ permalink ]

   • https://en.wikipedia.org/wiki/Floating-point_arithmetic
   • https://standards.ieee.org/standard/754-2008.html
   • https://stackoverflow.com/questions/588004/is-floating-point-math-broken/588014#588014
   • https://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html
3. Lenovo Thinkpad 13 + Linux - Feedback 2017-04-15

   tags: fan, hardware, hardware/cpu, heat, laptop, lenovo, linux, noise

   [ permalink ]

   +++: backlit keyboard, battery ++: HDPI matte screen, touchpad+trackpad -: BIOS messages in approximative English --: no ethernet port ---: cooling / fan noise

   ETH available through:

   • 10$ generic USB-C adapter
   • 25$ Lenovo USB-C adapter
   • 150$ Lenovo USB-C dock
   • 180$ Lenovo docking station

   Cooling / fan control:

   • triggered when the CPU reaches approx. 46° / 20% load
   • slowest speed: 3400 RPM (!), goes up to 4000+ RPM

   TODO:

   • try updating BIOS/UEFI
   • use a laptop cooling pad
   • killall -9 firefox # not really an option tho

   User-contributed feedback:

   • https://www.reddit.com/r/thinkpad/comments/4k2kzl/debian_on_the_thinkpad_13/
   • https://www.reddit.com/r/thinkpad/comments/4jh3wb/thinkpad_13_manjaroarch_impressions/
   • https://www.reddit.com/r/thinkpad/comments/4lzsks/my_thinkpad_13_experience_with_ubuntu_1604/
   • https://www.reddit.com/r/thinkpad/comments/4pieti/thinkpad_13_fan_vs_zenbook/