[Rd] Questions/suggestions about new staged installation

[Pages, Herve]

Hi,

I was playing around with inotifywait (great tool!) to see the new 
staged installation of source packages in action. In one terminal I'm 
monitoring the create/delete/move events of the installation library with:

   inotifywait -m --timefmt '%F %T' --format '%T -- %w %e %f' -e create 
-e delete -e move path/to/R/library/

While in another terminal I install CRAN package abc with:

   R CMD INSTALL abc_2.1.tar.gz

All deps are already installed.

## With R 3.5

When installing abc the first time with R 3.5 inotifywait reports the 
following events:

2019-04-24 16:57:42 -- /home/hpages/R/R-3.5.r75051/library/ CREATE,ISDIR 
00LOCK-abc
2019-04-24 16:57:42 -- /home/hpages/R/R-3.5.r75051/library/ CREATE,ISDIR abc
2019-04-24 16:57:45 -- /home/hpages/R/R-3.5.r75051/library/ DELETE,ISDIR 
00LOCK-

Then on subsequent times:

2019-04-24 16:58:14 -- /home/hpages/R/R-3.5.r75051/library/ CREATE,ISDIR 
00LOCK-abc
2019-04-24 16:58:14 -- /home/hpages/R/R-3.5.r75051/library/ 
MOVED_FROM,ISDIR abc
2019-04-24 16:58:14 -- /home/hpages/R/R-3.5.r75051/library/ CREATE,ISDIR abc
2019-04-24 16:58:17 -- /home/hpages/R/R-3.5.r75051/library/ DELETE,ISDIR 
00LOCK-abc

IIUC the additional 'MOVED_FROM,ISDIR abc'  event on subsequent installs 
is triggered by the backing up of the earlier installation in case the 
new installation fails.

## With R 3.6

First installation:

2019-04-24 17:09:04 -- /home/hpages/R/R-3.6.r76385/library/ CREATE,ISDIR 
00LOCK-abc
2019-04-24 17:09:04 -- /home/hpages/R/R-3.6.r76385/library/ CREATE,ISDIR abc
2019-04-24 17:09:08 -- /home/hpages/R/R-3.6.r76385/library/ 
MOVED_TO,ISDIR abc
2019-04-24 17:09:09 -- /home/hpages/R/R-3.6.r76385/library/ DELETE,ISDIR 
00LOCK-abc

Subsequent installations:

2019-04-24 17:09:59 -- /home/hpages/R/R-3.6.r76385/library/ CREATE,ISDIR 
00LOCK-abc
2019-04-24 17:09:59 -- /home/hpages/R/R-3.6.r76385/library/ 
MOVED_FROM,ISDIR abc
2019-04-24 17:09:59 -- /home/hpages/R/R-3.6.r76385/library/ CREATE,ISDIR abc
2019-04-24 17:10:02 -- /home/hpages/R/R-3.6.r76385/library/ 
MOVED_TO,ISDIR abc
2019-04-24 17:10:03 -- /home/hpages/R/R-3.6.r76385/library/ DELETE,ISDIR 
00LOCK-abc

IIUC the new 'MOVED_TO,ISDIR abc' event is triggered by the package 
installation folder being moved from the temporary location to the final 
location.

However I wonder about the CREATE,ISDIR abc event. It looks like even 
for a staged installation tools:::.install_packages() still creates the 
empty abc dir. This should no longer be necessary because this empty 
folder is replaced later by the 'MOVED_TO,ISDIR abc' event. Am I missing 
something?

Another thing: the times indicate that the 'MOVED_TO,ISDIR abc' event 
(move from temp to final location) happens about 3-4 seconds after the 
'MOVED_FROM,ISDIR abc' event (backing up). In this interval of time, the 
abc package is missing. Wouldn't it be safer to leave the earlier 
installation where it is and to replace it when the new installation 
folder is moved from the temporary location to the final location? Said 
otherwise, the backing up step no longer seems necessary with staged 
installs. So inotifywait would report something like this:

2019-04-24 17:09:59 -- /home/hpages/R/R-3.6.r76385/library/ CREATE,ISDIR 
00LOCK-abc
2019-04-24 17:10:02 -- /home/hpages/R/R-3.6.r76385/library/ 
MOVED_TO,ISDIR abc
2019-04-24 17:10:03 -- /home/hpages/R/R-3.6.r76385/library/ DELETE,ISDIR 
00LOCK-abc

That is, only 3 events. On first and subsequent installation.

Cheers,

H.


 > sessionInfo()
R version 3.6.0 beta (2019-04-12 r76385)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 16.04.5 LTS

Matrix products: default
BLAS:   /home/hpages/R/R-3.6.r76385/lib/libRblas.so
LAPACK: /home/hpages/R/R-3.6.r76385/lib/libRlapack.so

locale:
  [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C
  [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8
  [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8
  [7] LC_PAPER=en_US.UTF-8       LC_NAME=C
  [9] LC_ADDRESS=C               LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods base

loaded via a namespace (and not attached):
[1] compiler_3.6.0


-- 
Hervé Pagès

Program in Computational Biology
Division of Public Health Sciences
Fred Hutchinson Cancer Research Center
1100 Fairview Ave. N, M1-B514
P.O. Box 19024
Seattle, WA 98109-1024

E-mail: hpages using fredhutch.org
Phone:  (206) 667-5791
Fax:    (206) 667-1319