Hi Erik,
The update looks fine.
On 3/5/20 12:21 PM, Erik Gahlin wrote:
Hi Roger,
Thanks for the feedback.
Runtime.exec doesn't take arg[0] as a separate parameter, so it may
make sense to not split it up in the event. For example, if plan is to
execute "hg clone url", but the user forgets to add "hg", then it will
look as if "clone" is the command, which could be confusing.
The main interface for launching processes is ProcessBuilder.
Runtime.exec is a legacy interface and no longer drives the terminology.
I will change the field name to 'command' to make it consistent with
the single arg form of Runtime.exec.
tnx
Regarding delimiters, I think there are two use cases. Making
something easy for humans to read and making it unambiguous for
machine parsing. Since comma, or comma space, might be part of an
argument, it is still unsafe for a parser. It would be possible to add
escape sequences, but then it would be even harder for humans to read,
which I think is the main use case. If we in the future would add
support for serializing a String[], we could add another field, i.e.
commandArray, which would work for machines without special parse logic.
understood, it wasn't clear what the focus of a string in the JFR stream
is intended to mean or how it would be interpreted. I'm thinking that
more and more it will be tools and AI's (not people) that will be
looking through the reams and reams of output at scale.
There is no ProcessEnd event today, but that is something that could
be added in the future. The exit status could be useful.
one step at a time.
Thanks, Roger
Updated webrev:
http://cr.openjdk.java.net/~egahlin/8222000/
Thanks
Erik
On 2020-03-05 15:27, Roger Riggs wrote:
Hi Erik,
Would the event be more useful if the executable arg[0] was a
separate field from the arguments?
Though I exect it depends on what is later evaluating the event fields.
If all of cmdarrray is being joined, then the event field name is
more appropriately
called 'command'; similar to the single arg form of Runtime.exec and
new ProcessBuilder(...).
A small point but the joining with ' ' space has the usual problem of
trying to parse out the arguments later.
using ',' comma might be less ambiguous. (and Arrays.toString).
Otherwise, looks fine to me.
Is there already a Process exited event? Its not quite as convenient
to instrument but useful if it captures the exit status. (ProcessImpl
- Windows and Linux versions).
Roger
On 3/5/20 9:10 AM, Erik Gahlin wrote:
Hi
Could I have review of a JFR event that is emitted when a process is
started from Java.
Bug:
https://bugs.openjdk.java.net/browse/JDK-8222000
Webrev:
http://cr.openjdk.java.net/~egahlin/8222000/
Testing:
tier1,tier2 + jdk/jdk/jfr
Thanks
Erik
