registry.db getting rather obese (> 600MB) and updates very slow. Anything to do?

[Ryan Schmidt]

On Jun 21, 2020, at 13:17, Ken Cunningham wrote:

> On one of my systems, 10.5 PPC, things are taking a long time when uninstalling a port - like 4-5 minutes of heavy tcl interpreter use.
> 
> The registry.db is pretty huge:
> 
> $ ls -la
> total 1286264
> drwxr-xr-x     7 root  admin        238 21 Jun 11:06 .
> drwxr-xr-x@   15 root  admin        510 18 Dec  2018 ..
> -rw-r--r--     1 root  admin          0 21 Jun 10:59 .registry.lock
> -rw-rw-r--     1 root  admin          0  1 Oct  2015 .turd_MacPorts
> drwxr-xr-x  2954 root  admin     100436 21 Jun 10:59 portfiles
> drwxr-xr-x   185 root  admin       6290 13 Jun 19:51 portgroups
> -rw-r--r--     1 root  admin  658564096 21 Jun 11:06 registry.db
> 
> 
> As you can see, this install has been going along for 5 years, so I guess some bitrot could occur. I’m sure I could blow out the installation and start fresh, but that’s not terribly trivial on 10.5 PPC with no functional buildbot. 
> 
> Is there something else I can do to put that registry.db on a diet?

Since the registry contains information about every port you have installed, and every file installed by those ports, it's natural that it will be larger the more ports you have installed. On our Catalina buildbot worker, for example, since they keep all ports installed, the registry is 1GB. If you don't have many ports installed, then that size of registry would be unexpected.

The registry doesn't immediately shrink if you uninstall a port, but after enough free space builds up in the registry MacPorts will perform the SQLite "vacuum" procedure to reclaim space. MacPorts does not print any status information to tell you when this is happening.

It is normal that it can take a long time for MacPorts to write the modified registry to disk after you've installed or uninstalled something if it is large because you have many ports installed, or if MacPorts happens to perform the vacuum procedure. How long would depend on the speed of your disk. The 300MB registry on my main Mac takes a few seconds to rewrite but that's on a fast SSD.


On Jun 22, 2020, at 00:28, Ken Cunningham wrote:

> I decided to do the obvious, backed up all the built software, and reinstalled everything.

Has that helped? Do you now have a much smaller registry with the same set of ports installed? If so that would be unexpected and might indicate a problem in how we're cleaning up the registry during normal use.