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2018/03/31 Pure Trance Volume 6 @ Great Northern, SF

π 2018-03-31 01:01 in Clubbing

Great trance lineup:

21.00 - 23.00 Gai Barone

23.00 - 00.30 Robert Nickson

00.30 - 02.30 Solarstone

02.30 - 04.00 Factor B

The room was indeed packed for this sold out event, and the addition of lasers was a very nice bonus:

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2018/03/23 Day Trip at Kirkwood with Johannes

π 2018-03-23 01:01 in Nsnow, Snow

We left around 05:00 and by the time we crossed 88, Caltrans had no news about them opening, or them even working on it. Sadly they were actually working on it, but failed to say anything about it. After we had well passed the junction point, I got an alert that Carson Spur had opened, so we took a very non obvious (which Johannes described as "scenic" :) ).

We got to Kirkwood 45mn later than needed due to the long detour, but still made it by 09:15 or so. Because cornice did not open until 10:00 or so, and the Wall not until noon-ish, we did not miss out too much despite arriving later than planned. The snow was packed powder due to the water content, but it was still powder. Better than sierra cement or ice :) Crowds were not terrible, thanks to it being a friday.

the wall was bombed a lot

we had a mix of sun, high wind and snow flurries

glad to see another smart snowboarder, with poles :)

Thanks Johannes for getting us there and back!

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2018/03/17 Gareth Emery's Laserface at Bill Graham, San Francisco

π 2018-03-17 01:01 in Clubbing

Awesome super duper show. More lasers = more awesome, never mind the great trance music Gareth's and Kristina Sky's before that.

starting them young, good on Gareth Emery

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2018/03/14 2.5 days of Muchos Powder in Kirkwood

π 2018-03-14 01:01 in Nsnow, Snow

I had been watching the weather forecast for a while, and drove to kirkwood just before the storm turned from rain to snow. I got there with my Tesla 90D in just 3h30, including an 18mn supercharger stop in Manteca. I ended up arriving with 10% battery left in record time, just as the rain was turning to snow:

Day #1 was nice and had a bit of sun to help see the nice powder. Almost everything opened that day, so lots of terrain with not too many people:

Day #2 didn't have sun for long, lots of good snows and self refilling tracks, but poor viz, high winds, and very cold:

everyone made a run to the Wall when cornice didn't open at 09:00 when it was supposed to

Day #3 was more difficult. Very cold too, snow storm most of the day, and kirkwood couldn't get stuff opened. They only opened 6 after a never ending 2H wait. The first tracks were nice, but open terrain was very limited.

2h wait to finally be allowed up a limited section of chair 6, that was disappointing

very hard snow, no more pictures

After only 2H of skiing, and talking to Jennifer about the show we had that evening, I decided to try and get home after one of the two roads out finally re-opened. By leaving at 13:30, that would have been plenty of time, but sadly while driving down carson pass, I made a judgement mistake which combined with heavy regenerative braking kicking in in the middle of a slippery downhill turn, caused me to understeer and drive into a snow bank. It took over 1h30 to get out

a nice Audi with 3 awesome guys who helped me shovel out, was unable to pull me out

Caltrans truck then slid into the audi and hit its front

snow plow slid off the road and got stuck, had to be towed out by caltrans scraper

finally the just arrived caltrans scraper had enough weight and torque to pull me out

The rest of the drive home was not fun, took me around 7.5h, includuing the 1.5h stuck in the snow bank. But that was nothing compared to the people driving up hwy 50 on a friday afternoon/night and who took hours and hours to get through the pass...

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2018/03/11 Nine Years of Solar Panels

π 2018-03-11 01:01 in Solar

It's been 3 years since I did the last report. Sadly PG&E isn't doing reliable true up statements anymore, and with the alternate electric companies that are proving our electricity now, it's unclear what we'd have been paying anymore.

Anyway, here are the numbers:

Year # PV Kwh PG&E Kwh Used House Kwh Used Yearly Bill EV (car) 2010 - #1 8503 1602 10105 -$39.87 2011 - #2 8813 1209 10022 -$38.80 2012 - #3 8402 674 9076 -$110.43 2013 - #4 8366 486 8852 -$134.06 2014 - #5 8840 -30 8810 -$210.74 2015 - #6 8665 1027 9692 -$41.38 2016 - #7 8437 1386 9823 ? 2017 - #8 8335 1910 10245 $26.21 613Kwh 2018 - #9 8665 1922 10250 ? 209Kwh

Total 76689 10186 86875 N/A 822Kwh

A few notes:

EV use is very low because I don't drive much and mostly charge at work

The amount of energy I charged the car with at home amounts to about 2400 miles

In 9 years we took about 10Mwh from the grid, or what we'd have used in a year before

Our panels made 76Mwh, which at an average of 25c/Kwh would have cost $19,000, but due to time of use pricing, they actually saved us around $21,750, which is getting quite close to the panel costs. If the average price was closer to 30c/Kwh (very possible with tiers), then we saved about $26,000, which is the full price of the panels.

2018/03/09 Btrfs Tips: Rescuing A Btrfs Send Receive Relationship

π 2018-03-09 01:01 in Btrfs, Linux

I had a problem when migrating disks and moving read only btrfs receive snapshots. I did a

btrfs snapshot dir1/Video_ro.20180220_21:03:41 dir2/Video_ro.20180220_21:03:41

which in turn broke the snapshot by making it read-write and losing the btrfs receive relationship (Received UUID)

Later, I wanted to re-establish the btrfs send/receive relationship since it was an 8TB subvolume, and I wanted to avoid having to copy back all the data I already had there. Simply making the destination snapshot read only again did not work

The solution was python-btrfs, and this code: https://github.com/knorrie/python-btrfs/commit/1ace623f95300ecf581b1182780fd6432a46b24d

gargamel:python-btrfs/examples# ./set_received_uuid.py 2afc7a5e-107f-d54b-8929-197b80b70828 31337 1234.5678 /mnt/btrfs_bigbackup/DS1/Video_ro.20180220_21:03:411G Current subvolume information: subvol_id: 94887 received_uuid: 00000000-0000-0000-0000-000000000000 stime: 0.0 (1970-01-01T00:00:00) stransid: 0 rtime: 0.0 (1970-01-01T00:00:00) rtransid: 0

Setting received subvolume...

Resulting subvolume information: subvol_id: 94887 received_uuid: 2afc7a5e-107f-d54b-8929-197b80b70828 stime: 1234.5678 (1970-01-01T00:20:34.567800) stransid: 31337 rtime: 1520488877.415709329 (2018-03-08T06:01:17.415709) rtransid: 255755

Then make it read-only again: gargamel:python-btrfs/examples# btrfs property set -ts /mnt/btrfs_bigbackup/DS1/Video_ro.20180220_21:03:41 ro true

But this didn't work: ABORT: btrfs send -p /mnt/btrfs_pool1/Video_ro.20180220_21:03:41 Video_ro.20180308_07:50:06 | btrfs receive /mnt/btrfs_bigbackup/DS1//. failed At subvol Video_ro.20180308_07:50:06 At snapshot Video_ro.20180308_07:50:06 ERROR: cannot find parent subvolume

You can see that with set_received_uuid.py, I set Received UUID to match UUID on the source:

gargamel:/mnt/btrfs_pool1# btrfs subvolume show /mnt/btrfs_bigbackup/DS1/Video_ro.20180220_21:03:41 DS1/Video_ro.20180220_21:03:41 Name: Video_ro.20180220_21:03:41 UUID: cb4f343c-5e79-7f49-adf0-7ce0b29f23b3 Parent UUID: 0e220a4f-6426-4745-8399-0da0084f8b23 Received UUID: 2afc7a5e-107f-d54b-8929-197b80b70828 << changed this Creation time: 2018-02-20 21:13:36 -0800 Subvolume ID: 94887 Generation: 250689 Gen at creation: 250689 Parent ID: 89160 Top level ID: 89160 Flags: readonly Snapshot(s):

Name: Video_ro.20180220_21:03:41 UUID: 2afc7a5e-107f-d54b-8929-197b80b70828 Parent UUID: e5ec5c1e-6b49-084e-8820-5a8cfaa1b089 Received UUID: 0e220a4f-6426-4745-8399-0da0084f8b23 Creation time: 2018-02-20 21:03:42 -0800 Subvolume ID: 11228 Generation: 4174 Gen at creation: 4150 Parent ID: 5 Top level ID: 5 Flags: readonly

Turns out however that because the source had a Parent UUID value too, I was actually supposed to set Received UUID on the destination to it:

gargamel:python-btrfs/examples# ./set_received_uuid.py 0e220a4f-6426-4745-8399-0da0084f8b23 313 37 1234.5678 /mnt/btrfs_bigbackup/DS1/Video_ro.20180220_21:03:41 Current subvolume information: subvol_id: 94887 received_uuid: 2afc7a5e-107f-d54b-8929-197b80b70828 stime: 1234.5678 (1970-01-01T00:20:34.567800) stransid: 31337 rtime: 1520488877.415709329 (2018-03-08T06:01:17.415709) rtransid: 255755

Setting received subvolume...

Resulting subvolume information: subvol_id: 94887 received_uuid: 0e220a4f-6426-4745-8399-0da0084f8b23 stime: 1234.5678 (1970-01-01T00:20:34.567800) stransid: 31337 rtime: 1520537034.890253770 (2018-03-08T19:23:54.890254) rtransid: 256119

gargamel:python-btrfs/examples# btrfs property set -ts /mnt/btrfs_bigbackup/DS1/Video_ro.201802 20_21:03:41 ro true

After this, I was able to re-start my btrfs send/receive and /mnt/btrfs_bigbackup/DS1/Video_ro.201802 20_21:03:41 was properly accepted as a destination. Yeah!

2018/03/03 5ft powder storm in Tahoe: Sierra @ Tahoe and Heavenly

π 2018-03-03 01:01 in Nsnow, Snow

After a horrible dry spell this year, Tahoe finally started getting a bit of snow. While 5ft in a storm sounds great, I got to find out that it was 5ft on top of almost nothing, so the tree runs were very treacherous. The amount of rocks and tree stumps, which ultimately isn't super safe. Also, the resorts were super packed, which is not surprising given that everyone had been waiting for real snow for so long.

Johannes was a trooper and offered to drive me to Tahoe, which was super great given that I had a concert on friday night and got to bed around 01:00. Sadly, my plan failed miserably and I slept past both my alarms for 05:00. Johannes was super nice and just waited for me to wake up (it's more complicated than this, but skipping details), and we ended up being on the road around 07:15. By then Carson Spur was still closed sadly (it only opened at 13:00, very late), so we ended up driving past Sierra @ Tahoe on hwy50 around 11:30 and figured it was already late enough that we might as well just go there. Sadly we didn't know the resort well and went to the famed West Bowl was actually kind of stupid because while it had plenty of snow, it was lacking slope. We later (too late) went to the main lift on the front side, and that gave much better terrain and pitch:

good enough for the day given that it was already 11:30

the tree runs I did were great, but honestly very technical, even for me

convertible RWD porsche without chains just after a snow storm, ballsy but well done

Since we were sleeping in South Lake, heavenly for day #2 was the easiest, but also I figured they'd have more untracked terrain than kirkwood, so we gave that a shot. Mott opened at 10:00 and I made the mistake of not being at the rope waiting for it to open, so I missed the first group down and it was half tracked for my first run. First line was about 30mn, second line was 40mn+. Yikes!

nice view as always

worst Mott line ever

people lined up the hill :( it almost took as long to line up than to hike up

peek-a-boo

oh no, tree skiing is bad :)

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2018/03/02 Above and Beyond A Bill Graham Theatre in SF

π 2018-03-02 01:01 in Clubbing

It had been a while since I had seen Above in Beyond in San Francisco doing club music (did see them last year for their Accoustic II tour which was great, but different for sure).

Sadly, despite the huge venue and amount of people, they only played 2H (compared to Armin or Tiesto who would do much longer sets in a specially rented venue like this), but still those 2 hours were really good, so there's that :)

it must hurt when the head gets sliced off

Video summary:

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