We apologize yet again for the lack of work over the past month and a half, since all of you had last BOINC'd to solve Minecraft’s tallest cactus mystery. Now, after improving Kaktwoos’ ease of use for our developers we are ready for one last, hopefully long round of cactus stacking and chunk smashing with our fellow cacti enthusiasts. Thanks to some changes behind the scenes, our developers no longer have to painfully modify many configuration files and verify multiple server adjustments (as mentioned in our previous post). At most now they will only have to change two numbers and send work out, as all of the preliminary seeds have been pre-loaded for BOINC to work off of! So, how much work do we expect to generate over the next few days?

Well for starters, an average run of ‘Kaktwoos’ per block layer (y-level) creates 120,000 tasks at a minimum, and each task takes a midrange gaming GPU at least an hour to complete. We have at least 10 layers planned to be checked for 23 and 24-block tall cacti, making this one of our most comprehensive searches yet. Even with 1000 users computing away 24/7, we can imagine this work, and reviewing all the data from it will take at least *60* days. This doesn’t even include that the seeds we are working on are only a fraction of the potential cacti to be stacked, though are the most likely to successfully merge into Tall Cacti at these unusual heights.

So, how high up in a desert do you think we can find tall cacti? Will ‘Superflat’ presets be the final destination for outrageously tall cacti searches? Join us now at Minecraft@Home to find out, and bring back immense compute power to our BOINC network! We recommend anyone with a Windows 7/10 64bit and Ubuntu 18.04 or newer OS to join, and especially those with an AMD RX 460, GTX 750ti or newer/faster. Intel Graphics are supported as well, and multiple GPU systems are in high demand and very capable to assist us. If you’re in the Northern Hemisphere feeling cold and isolated this winter, why not BOINC with us and chat in our Discord server https://discord.gg/xArErFf , or pay a visit to our messaging board?

If you have already begun the penultimate search for ‘stacctus’ with us already, try to find your own tall cacti under ‘Your Tasks’ in the BOINC client’s ‘Advanced View’, then by clicking on the task number inside your browser. Inside those logs maybe there’s a chance you’ll find a 22 or taller ‘natural’ cactus of your own, that you can build by and share with us. We will be posting updates often to announce any interesting findings from your hard work, so stay tuned in the upcoming weeks for more.

Thanks Neil, some additional info on what this means:

With the last batch of Kaktoos work you had done in November/December, we have prepared more Kaktwoos tasks and uploaded all the seed data (cacti) we can reasonably use to make a tall cactus. So now, we will be running through as many layers as we can believe to be worth it, or give us a chance to find unreasonably tall cacti.

At the moment, we have generated around 130,000 initial tasks for everyone on BOINC to work with us through. This will search through all of block height 64 and was the next, most likely height to find new record-setting cacti. I suspect we will re-run parts of y=62 and y=63 (original run) as well with some other cacti to see if we can re-confirm or add to our previous results, but *only* looking for 22-block tall or higher. In the short-term (as in, 1-2 months) will we load up heights of y=65-y70 to begin 'Phase 1' of our final search. Each y-level makes it incredibly difficult to find another tall cactus due to us having to merge cacti from two adjacent chunks of the same height together. If sand or anything overlaps off-axis, then stacking fails, or doesn't go as planned.

Below though is our first tall Superflat cactus at y=64! Say hello!

(Found by user 'Jas:10284893' and Matt/Kappa from Discord)

Sadly, this cactus didn't reach its full potential due to that dry bush nearby, sapping its growth (figuratively and literally) due to failed placement pre-stacking.
To Kaktwoos, this was a 22-Tall, but to us in reality it was only 17 blocks in a Superflat desert. As the entire nature of Tall Cacti is random and almost all luck-based, disappointments like this can and do happen.

Hi again to everyone who is reading this and/or working with us (Minecraft@Home) to find the tallest cacti, and document as many 22+ height cacti in Minecraft. We're now about 35% through our first workload (y=64) and have collected over 90 unique Superflat-category Cacti seeds and coordinates, as well as around two natural-gen failed tall cacti. While this sounds like bad news, we have been working on and using some software that is making it much easier to verify which cacti can generate naturally or not (once your tasks post cactus seeds to validate). Additionally, we have been testing some new optimizations from the talented 'Balint', who originally worked with me and our administrator Chip to port Kaktwoos to OpenCL and to as many GPUs as possible.

Without promising anything, if our testing goes in the direction we hope (faster, not slower) we may be able to speed up the majority of AMD GPUs by between 30-50%. I have verified this myself with my Vega 56, where it now runs at an impressive '60m/s'; 60 million seeds per second from 40. An RX 480 has increased to near GTX 1070 levels of compute for kaktwoos, being 25m/s vs GTX's 30m/s or so. A RTX 3090 though stands between 220-300 million seeds per second, depending on if it is dedicated for compute or as a gaming/display card while it is running kaktwoos. Sadly, these OpenCL kernel changes do not play as consistently on Nvidia hardware, where a RTX 2060 gained from 50 to 60m/s speed, but yet an RTX 3090 lost 5%. While this didn't seem terrible, my laptop GTX 1650 (50m/s) was crippled to 33m/s while using the attempted optimizations. Oh yeah things are gonna be good.

Due to the nature of BOINC, we cannot (currently) assign sets of GPUs (outside of vendor) to use a certain kernel, and thus these optimization attempts cannot be made universal (and hope is now placed on good RX 5700/6800 results). AMD makes up 35-40% of our compute base, and so that would make these users much more competitive, in both searching for cacti and completing tasks for credits faster.

Otherwise, here's some statistics on how awfully improbable it is to find a *potential* tall-cacti now:
We've found 8 23-tall cacti so far in our current run and 69 22-tall (so far, these aren't validated either) out of 15,317~ unique tasks/workunits validated. in other words, finding a 23-tall cacti is a 0.0005-0.0006 likelihood even at the 'better but not best' y=64 layer.

Until the next update (in a few days), have some misc. cacti:

The 2nd Natural-Gen cactus found by our 'new' validator, but sadly in pieces due to caves in the chunk causing chaos!


I tried out the python 'deep_daze' image gen neural net with the phrase "a tall green cactus in a desert" as an input, and let it run on Google Colab. Funnily enough, the longer it ran, the taller this cacti got. Seems like kaktwoos isn't the only GPU Compute application that can stacc the cact!

Hi again to everyone who is reading this and/or working with us (Minecraft@Home) to find the tallest cacti, and document as many 22+ height cacti in Minecraft. We're now about 35% through our first workload (y=64) and have collected over 90 unique Superflat-category Cacti seeds and coordinates, as well as around two natural-gen failed tall cacti. While this sounds like bad news, we have been working on and using some software that is making it much easier to verify which cacti can generate naturally or not (once your tasks post cactus seeds to validate). Additionally, we have been testing some new optimizations from the talented 'Balint', who originally worked with me and our administrator Chip to port Kaktwoos to OpenCL and to as many GPUs as possible.

Without promising anything, if our testing goes in the direction we hope (faster, not slower) we may be able to speed up the majority of AMD GPUs by between 30-50%. I have verified this myself with my Vega 56, where it now runs at an impressive '60m/s'; 60 million seeds per second from 40. An RX 480 has increased to near GTX 1070 levels of compute for kaktwoos, being 25m/s vs GTX's 30m/s or so. A RTX 3090 though stands between 220-300 million seeds per second, depending on if it is dedicated for compute or as a gaming/display card while it is running kaktwoos. Sadly, these OpenCL kernel changes do not play as consistently on Nvidia hardware, where a RTX 2060 gained from 50 to 60m/s speed, but yet an RTX 3090 lost 5%. While this didn't seem terrible, my laptop GTX 1650 (50m/s) was crippled to 33m/s while using the attempted optimizations. Oh yeah things are gonna be good.

Due to the nature of BOINC, we cannot (currently) assign sets of GPUs (outside of vendor) to use a certain kernel, and thus these optimization attempts cannot be made universal (and hope is now placed on good RX 5700/6800 results). AMD makes up 35-40% of our compute base, and so that would make these users much more competitive, in both searching for cacti and completing tasks for credits faster.

Otherwise, here's some statistics on how awfully improbable it is to find a *potential* tall-cacti now:
We've found 8 23-tall cacti so far in our current run and 69 22-tall (so far, these aren't validated either) out of 15,317~ unique tasks/workunits validated. in other words, finding a 23-tall cacti is a 0.0005-0.0006 likelihood even at the 'better but not best' y=64 layer. space bar clicker

Until the next update (in a few days), have some misc. cacti:

The 2nd Natural-Gen cactus found by our 'new' validator, but sadly in pieces due to caves in the chunk causing chaos!


I tried out the python 'deep_daze' image gen neural net with the phrase "a tall green cactus in a desert" as an input, and let it run on Google Colab. Funnily enough, the longer it ran, the taller this cacti got. Seems like kaktwoos isn't the only GPU Compute application that can stacc the cact!

Hy, I appreciate the update and summary.