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Why does everyone run ancient Postgres versions?

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Re: Why does everyone run ancient Postgres versions?

#161

Post by sunnybeetroot »

Dalewyn wrote: post #128
atoav wrote: post #123

Earlier quoted context omitted.

Also: 5. If your IT department is spread thin already and that old version is running fine, the incentive to potentially create more work for yourself is not gigantic.

One of the first laws of the universe that a good engineer learns is: Do not fix what is not broken. And no, being old is not broken.

I do agree, however I think it’s often easier to upgrade iteratively and deal with smaller issues that arise as opposed to upgrading a huge version diff and struggling to understand and fix all the failing parts.

Re: Why does everyone run ancient Postgres versions?

#162

Post by buro9 »

Upgrading isn't automatic.

Let me check what I'm on... brb... Postgres 14.

Because it's not automatic I leave it, I leave it until it's so unsupported that I must upgrade the whole system, then I build a new system with a new Postgres and I migrate the old to the new.

I want, so badly, for Postgres to just automatically update itself, that a new binary just works with the data directory of an old version, and that if required it does an in-place upgrade to those data files when it can (i.e. if it can detect the last version was the same major as the current version, upgrade the files transparently to the admin).

My databases are all backed up each night, and these are single server Postgres with no replication or other trickery, an automatic upgrade for a single-server Postgres should be possible.

As it's not done... I assume (incorrectly?) that there be dragons and risks, and I mitigate that by never upgrading, just waiting and migrating. Migrating puts all of the risk on me, human error, and I am definitely fallible, so I can best handle this risk by just not doing it until I must.

Last migration I performed was from Postgres 7 > Postgres 14 in October 2021... I guess I have quite a few years of Postgres 14 ahead of me still. I would take downtime, my systems aren't zero downtime critical, just give me a super simple one-command no-questions upgrade as I really dislike migrations.

Re: Why does everyone run ancient Postgres versions?

#164

Post by atoav »

Dalewyn wrote: post #128
atoav wrote: post #123

Earlier quoted context omitted.

Also: 5. If your IT department is spread thin already and that old version is running fine, the incentive to potentially create more work for yourself is not gigantic.

One of the first laws of the universe that a good engineer learns is: Do not fix what is not broken. And no, being old is not broken.

This is solid advice, however I would caveat that you can't know if it is broken if you are not checking. E.g. if your old as hell database has a known vulernability that can be expoited, unless you can rule out that it can be used in your setup it is broken by all definitions of the word.

Re: Why does everyone run ancient Postgres versions?

#165

Post by KronisLV »

In many orgs out there, the version that's picked when a project is started will stick around for a while.

Suppose you join a project and see that the PostgreSQL version used is pretty old.

Do you:

  A) convince people to migrate it for some nebulous benefits (features that aren't currently used, performance improvements that will be difficult to measure in lieu of tooling and aggregated statistics) while also taking on the risks of breaking everything or even worse, data loss (since you won't always be able to provision multiple instances and backup restore might take a while and you could still mess that up)
  B) or just leave it as it is and focus on anything else
Many will prefer to not get burned even if there shouldn't be that many risks with upgrading your average PostgreSQL install, which is why you'll get minor/patch releases as best, alongside whatever the runtime environment is getting upgraded.

Containers and bind mounts make all of this way easier, but then again, many places don't use containers.

Re: Why does everyone run ancient Postgres versions?

#166

Post by nomercy400 »

For me it is a data vs code thing.

If I run my application/code v1 right now, I generate data. I expect that if I move to application/code v2, I can leave my data in place and it will automatically apply changes to my data.

I do not get that with postgres. If I am on postgres 16, and I want to upgrade to postgres 17, I want to leave my data folder untouched. When I then start postgres 17, it should just work (tm).

It should also work with code that assumes postgres 16, so I can upgrade my database separate from my application. I can not wait 10 days for a large database to be migrated from 16 to 17 without being able to run it. However, I can wait 10 days before updating my code to support features in 17.

The current upgrade process does not give me such confidence in restoring data and uptime. So I don't upgrade until I really have to.

Re: Why does everyone run ancient Postgres versions?

#167

Post by iamjkt »

pritambarhate wrote: post #120
sgarland wrote: post #74

Earlier quoted context omitted.

They’re not wrong. If you’ve ever spent meaningful time administering both, you’ll know that Postgres takes far more hands-on work to keep it going. To be clear, I like both. Postgres has a lot more features, and is far more extensible. But there’s no getting around the fact that its MVCC implementation means that at scale, you have to worry about things that simply do not exist for MySQL: vacuuming, txid wraparound,…

My experience has been exactly opposite. Ability to do Vacuums is good. MySQL doesn’t free up space taken by deleted rows. The only option to free up the space is to mysqldump the db and load it again. Not practical in most of the situations.

Running 'optimize table ' reclaims the space on MySQL/MariaDB.

Re: Why does everyone run ancient Postgres versions?

#168

Post by MaKey »

thrdbndndn wrote: post #116
sofixa wrote: post #112

Earlier quoted context omitted.

> I have trouble updating packages (that aren't install via pip/npm/cargo) on Linux all the time as a newbie. The experience is worse than Windows for some reason If you haven't installed them via your programming language's package manager, you either installed them manually or via the OS package manager. The first one you'd know how to upgrade, and for the second you can ask it what version it is and what version i…

Not exactly random. It's not hard to tell which website is official 7-zip website. Also choco and scoop exist on Windows. > As good as the worst possible option on Linux. I understand this is not a fair comparison, but in practice, they're not as easy. When using Windows, I usually use it with a proper GUI interface, so popping up a browser and download the newest installer for a software from their official website…

> Doing similar for my Linux VPS with only a terminal is much more complicated.

sudo apt-get install p7zip-full

Re: Why does everyone run ancient Postgres versions?

#169

Post by elric »

sunnybeetroot wrote: post #161
Dalewyn wrote: post #128

Earlier quoted context omitted.

One of the first laws of the universe that a good engineer learns is: Do not fix what is not broken. And no, being old is not broken.

I do agree, however I think it’s often easier to upgrade iteratively and deal with smaller issues that arise as opposed to upgrading a huge version diff and struggling to understand and fix all the failing parts.

I think there's a balance to be struck there. On large databases, upgrade time can be very slow. Is it worth upgrading iteratively at great expense if there are no benefits to be gained (e.g. no bugfixes that affect you, no critical security issues)? Maybe, maybe not.

Re: Why does everyone run ancient Postgres versions?

#170

Post by xpasky »

heavyset_go wrote: post #6
xpasky wrote: post #5

Related... postgres 1958 0.0 0.0 247616 26040 ? S Jul21 3:03 /usr/lib/postgresql/11/bin/postgres postgres 1085195 0.0 0.0 249804 24740 ? Ss Aug19 2:01 /usr/lib/postgresql/13/bin/postgres postgres 1085196 0.0 0.0 223240 27900 ? Ss Aug19 1:59 /usr/lib/postgresql/15/bin/postgres Postgres is the only thing on my Debian that doesn't seamlessly automatically upgrade across dist-upgrades, but instead leaves old versions aro…

That's because you install versioned packages like postgresql-15: https://tracker.debian.org/pkg/postgresql-15 That way you can have multiple versions of the same package.

You mean there is some other way to install postgresql in Debian?
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