4 ms·

make everything UTC, people. It'll make your life way easier. Try it out.

Too 5y ago
Internally yes, this is a no brainer. However in log files that are often read directly by humans, who want to see things in local time, it can become a balance and you might need to fight some admins for it. A proper structural logging system solves this, but log files on disk and other ad-hoc diy logs is still extremely common to see.
- guipsp 5y ago
  Just live in GMT+0. Easy!
  - alephnil 5y ago
    I have sometimes put my computer in the Iceland time zone for that reason when using dual boot with Linux, since Linux prefer to run UTC on the clock, and the Iceland time zone is UTC+0 with no daylight saving time. Making windows believe it is in Iceland make sure it does not mess up the clock. Though it is possible to set windows to UTC too with the same effect.
- gpderetta 5y ago
  Especially in log files I want to see UTC. When you have servers all around the world, I do not want to figure out what timezone was the specific server running in nor I want to convert between timezones when comparing logs of different servers.
- barrkel 5y ago
  On-disk logs should use ISO-8601 in UTC, ideally first thing on the line. That way you can merge them from different sources and sort them to help figure out interactions and causality. There might be clock drift from different sources but that's a much smaller problem than trying to eyeball multiple different logs concurrently, or write ad-hoc scripts to enable merging.
  - Too 5y ago
    For pure servers, what you say is easy and yes, almost exclusively, the preferred option. The tricky situations usually occur in CI, where you script together a lot of weird tools, most of them originally designed to be run by hands on developers workstation, where they want to see local timestamps and never had time to implement log config. Some days you can consider yourself lucky if the log files have any timestamps at all.
EsotericAlgo 5y ago
One especially frustrating version of this is a log or the like reporting a time as UTC but it’s not. So close.
AYBABTME 5y ago
Still need the timezone in the timestamp, UTC or not.
BurningFrog 5y ago
This is good advice, but ONLY for timestamps. When people try to apply this to other time related info, it's always a disaster.
makeitdouble 5y ago
Only if literally _everything_ is UTC. If you can’t go that far and still need local time zones in some specific part, just embrace your fate and keep and display timezones everywhere, even when it’s UTC. TBH, I’ve never seen an organization that could 100% move everything to UTC. Especially with countries following DST and other shenanigans, and you want to quickly be able to compare events at the same local time.
- kristopolous 5y ago
  Use timezones as an interface accommodation and not a storage format. If you're going to do it in storage, keep it outside the ISO/8601 string. Chronology is the most important thing to get right. Locality comes after
sleepydog 5y ago
Absolutely. I support this 100%. But even if everything is in UTC, please, please make sure that it's clear that the time is UTC. That could mean an ISO 8601 timestamp with 'Z' or '+0' at the end, or a 'UTC' in the corner of your graph, or using unix timestamps. Unless the whole world agrees to communicate times in UTC, at some point, you will share a screenshot or a log message with someone outside of your company, and they cannot assume what time zone it's in.

Too 5y ago

Internally yes, this is a no brainer. However in log files that are often read directly by humans, who want to see things in local time, it can become a balance and you might need to fight some admins for it. A proper structural logging system solves this, but log files on disk and other ad-hoc diy logs is still extremely common to see.

guipsp 5y ago
Just live in GMT+0. Easy!
- alephnil 5y ago
  I have sometimes put my computer in the Iceland time zone for that reason when using dual boot with Linux, since Linux prefer to run UTC on the clock, and the Iceland time zone is UTC+0 with no daylight saving time. Making windows believe it is in Iceland make sure it does not mess up the clock. Though it is possible to set windows to UTC too with the same effect.
gpderetta 5y ago
Especially in log files I want to see UTC. When you have servers all around the world, I do not want to figure out what timezone was the specific server running in nor I want to convert between timezones when comparing logs of different servers.
barrkel 5y ago
On-disk logs should use ISO-8601 in UTC, ideally first thing on the line. That way you can merge them from different sources and sort them to help figure out interactions and causality. There might be clock drift from different sources but that's a much smaller problem than trying to eyeball multiple different logs concurrently, or write ad-hoc scripts to enable merging.
- Too 5y ago
  For pure servers, what you say is easy and yes, almost exclusively, the preferred option. The tricky situations usually occur in CI, where you script together a lot of weird tools, most of them originally designed to be run by hands on developers workstation, where they want to see local timestamps and never had time to implement log config. Some days you can consider yourself lucky if the log files have any timestamps at all.

EsotericAlgo 5y ago

One especially frustrating version of this is a log or the like reporting a time as UTC but it’s not. So close.

AYBABTME 5y ago

Still need the timezone in the timestamp, UTC or not.

BurningFrog 5y ago

This is good advice, but ONLY for timestamps. When people try to apply this to other time related info, it's always a disaster.

makeitdouble 5y ago

Only if literally _everything_ is UTC. If you can’t go that far and still need local time zones in some specific part, just embrace your fate and keep and display timezones everywhere, even when it’s UTC. TBH, I’ve never seen an organization that could 100% move everything to UTC. Especially with countries following DST and other shenanigans, and you want to quickly be able to compare events at the same local time.

kristopolous 5y ago
Use timezones as an interface accommodation and not a storage format. If you're going to do it in storage, keep it outside the ISO/8601 string. Chronology is the most important thing to get right. Locality comes after

sleepydog 5y ago

Absolutely. I support this 100%. But even if everything is in UTC, please, please make sure that it's clear that the time is UTC. That could mean an ISO 8601 timestamp with 'Z' or '+0' at the end, or a 'UTC' in the corner of your graph, or using unix timestamps. Unless the whole world agrees to communicate times in UTC, at some point, you will share a screenshot or a log message with someone outside of your company, and they cannot assume what time zone it's in.