Notes – ANDREW PENG

Update your Nexus 5 to 5.1.1 Without Losing Data

May 26, 2015 No Comments

Android Lollipop 5.1.1 was recently released for the Nexus 5 as a maintenance update to the latest OTA update of 5.1.0 to fix numerous issues, such as an intermittent non-response camera and excessive memory usage leading to crashing applications.

If you have a rooted phone or a phone with a custom recovery, you may find that the OTA update doesn’t work on your phone – this is because the update process now checksums and verifies partitions such as recovery before performing the update. If the partitions don’t match the expected stock ROM, the update process will terminate. Having a rooted phone (with the su binaries), modified radio, modified recovery, or custom ROM may all contribute to an update failing and bombing out.

Cool!, Notes

Texas Front License Plate Laws

October 3, 2014 6 Comments

Let me preface this with the fact that I am not a lawyer, nor should anything in this post be taken as legal advice. Use the information provided here at your own risk.

In researching the front license plate law I found a lot of conflicting information on the requirements of how and where the front license plate can be put on a car that is registered in Texas. I spent a few minutes digging around the Internet looking at credible sources of information (such as published Texas laws and statues from the Texas state legislature.

Notes

Subaru Spherical Bushing Retrofit on 2008-2010 STi

September 10, 2014 No Comments

From 2008 to 2010, Subaru used a rubber bushing for the front control arm rear on the STi (and probably other models based on the same suspension setup like the WRX and Impreza). The benefit of rubber in the bushing is a soft compliant feel with very low NVH. However, due to the design of the bushing and the extreme angles that the control arm has to articulate – the bushings quickly deteriorate.

This was solved in the 2011 model year STi – Subaru moved to a spherical bushing for the front control arm rear. This part is easily retrofitted to 2008 to 2010 STi models with the following part numbers:

2x 901000377 – BOLT FLG 14
1x 20202FG042 – ARM ASSY F ALUMI RH
1x 20202FG052 – ARM ASSY F ALUMI LH

Everything is a bolt-on affair and the control arms also include a new ball joint.

There is a slight increase in NVH, but the spherical bearing lasts much longer and provides much more precise control than the old style rubber bushings.

Notes, Pictures

4G LTE Battle Showdown: Sprint vs. AT&T vs. T-Mobile

February 25, 2014 No Comments

Sitting in a cafe in Austin gave me the perfect opportunity to have a 4G LTE showdown. I have a Nexus 5 on Sprint’s 4G LTE service, and my girlfriend has a Nexus 5 on AT&T’s 4G LTE and a Nexus 7 on T-Mobile’s 4G LTE. We all did a speedtest. Results below.

Notes, Pictures

Bulging Capacitors

December 25, 2013 No Comments

My workstation had been experiencing a lot of instability lately. Decided to tear it down and look for issues, and look at what I found:

Notes, Pictures

Sprint 4G LTE in Houston

November 12, 2013 No Comments

Notes

2^128 is a really big number

August 2, 2011 No Comments

~ $ dig andrewpeng.net aaaa +short
2607:f298:1:104::a53:ecdd

~ $

What the hell is that? It’s my shiny new IPv6 address! Dreamhost makes it stupid easy to assign a IPv6 address to your account; just log into your panel, click on your domain, then just click Add IP Address and that’s it.

I also added an AAAA record for ipv6.andrewpeng.net to make sure to make the distinction for the IPv6 only subdomain, similar to ipv6.google.com and such. If you have IPv6 connectivity, go ahead and give it a try!

Linux/Command Line Hero, Notes

Crisis Averted

July 22, 2011 No Comments

Really thought I lost the LVM share. There might actually be a bug in the PowerPC Debian kernel that causes it to kernel panic on large LVM partitions. Ever since I switched to an Athlon MP server from my old PowerMac, it hasn’t kernel panicked since. Nice to have a large network drive at home again. Gonna take the plunge and convert the partition to ext4 while I’m at it.

pengc99@zeus:~$ sudo fsck.ext4 -fvy -C 0 /dev/mapper/MASS_STORAGE-STORAGE_LV
e2fsck 1.41.12 (17-May-2010)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information

342541 inodes used (0.19%)
1892 non-contiguous files (0.6%)
178 non-contiguous directories (0.1%)
# of inodes with ind/dind/tind blocks: 57159/9867/16
333728343 blocks used (91.11%)
0 bad blocks
57 large files

321274 regular files
21258 directories
0 character device files
0 block device files
0 fifos
0 links
0 symbolic links (0 fast symbolic links)
0 sockets
——–
342532 files
pengc99@zeus:~$

Cool!, Life, Notes, Pictures

A Legacy Concluded

July 12, 2011 No Comments

[Source: arockalypse on Reddit / Flickr]

Cool!, Notes, Video, Wait, what?

Be nice to your servers

July 1, 2011 No Comments

httpv://www.youtube.com/watch?v=tDacjrSCeq4

Yelling at your servers can measurably negatively affect their performance. No joke. Make sure to treat your servers with respect, and keep it quiet in the datacenter!

Perhaps there is a “brown note” for disks (“rust note”?) – some harmonic that destroys their performance; although based on what we think is happening (disk heads being thrown off track), we think this has more to do with shock force than resonance. I’m sure there are disk vendor engineers out there who know all about this (Bryan links to a good reference in his blog entry).

[Source: Sun Microsystems Blog (now Oracle)]