@@ -252,13 +252,17 @@ Blessings are used:
flight. (Flights with blessing `foo' use only hosts which have
flag `blessed-foo'.)
-Each flight has a `blessing' and an `intended blessing'. The
-`intended blessing' is what the flight is going to be blessed as when
-its execution has completed. The intended blessing controls host
-allocation.
-
-(Normally the `intended blessing' is the same as the bless argument to
-sg-execute-flight aka the -B argument to mg-execute-flight.)
+Each flight has a `blessing' (flights.blessing in the DB) and an
+`intended blessing' (flights.intended). The `blessing' changes as the
+flight goes through the stages of its lifecycle. The `intended
+blessing' is roughly what the flight is going to be blessed as when
+its execution has completed, and controls host allocation.
+
+There is also the blessing which the flight will actually get when it
+is finished, which is not represented in the DB; rather, it is the
+blessing argument to sg-execute-flight (aka the -B argument to
+mg-execute-flight). Normally this is the same as the intended
+blessing in the DB, except for bisection flights.
These are the principal (intended) blessings:
@@ -297,9 +301,9 @@ These are the principal (intended) blessings:
when the hosts are ready.
* `real-bisect' and `adhoc-bisect': These are found only as the
- blessing of finished flights. (This is achieved by passing *-adhoc
- to sg-execute-flight.) This allows the archaeologist tools to
- distinguish full flights from bisection steps.
+ blessing of finished flights. (This is achieved by passing
+ *-bisect to sg-execute-flight.) This allows the archaeologist
+ tools to distinguish full flights from bisection steps.
The corresponding intended blessing (as found in the `intended'
column of the flights table) is `real'. So the hosts used by the
@@ -320,6 +324,16 @@ There are also blessings for unfinished flights:
* `broken': Something went catastrophically wrong.
+ * `broken-*': Conventionally set by hand when a flight needs to be
+ `un-blessed', perhaps because it contains data misleading to the
+ archaeologists.
+
+ A flight's blessings can be manually changed with cs-flight-bless:
+ ./cs-flight-bless FLIGHT broken-real real
+ updates FLIGHT to be marked `broken' rather than `real'.
+ (cs-flight-bless matches the existing blessing against its final
+ argument, to avoid accidents.)
+
Note that osstest is generally `crash-only software': nothing will
`clean up' a crashed flight and set its blessing to `broken'. Flights
which were in progress once upon a time but never completed, because
@@ -328,8 +342,3 @@ time.
There is a special exception to the tools' flight status checks: any
flight whose blessing contains `play' can be operated on out of order.
-
-Flights blessings can be manually changed with cs-flight-bless. Eg
- ./cs-flight-bless FLIGHT broken-real real
-updates FLIGHT to be marked `broken' rather than `real'. This can be
-useful if a flight's data is misleading to the archaeologists.
--
1.7.10.4
From d677a8bfe576b44d28df4d5d62cbe9dec9fd5578 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ian.jackson@eu.citrix.com>
Date: Thu, 17 Dec 2015 16:51:17 +0000
Subject: [OSSTEST PATCH] README.dev: Document the blessings
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
---
v2: Improvements from review
---
README.dev | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 110 insertions(+)
@@ -232,3 +232,113 @@ probably are after a reboot) by looking for processes relating to the
lists flight,job combinations and then:
$ ./mg-hosts previoustasks --clear
+
+
+Flight blessings and the blessed-* host flags
+=============================================
+
+Both flights and hosts have a `blessing'.
+
+Blessings are used:
+
+ * To avoid accidentally tools operating on flights which are in the
+ wrong phase of their existence.
+
+ * To control which automatic archaeologists will look at which
+ flights. (Archeaology tools take arguments to control which
+ blessings they will consider.)
+
+ * To control which hosts are considered suitable for use with which
+ flight. (Flights with blessing `foo' use only hosts which have
+ flag `blessed-foo'.)
+
+Each flight has a `blessing' (flights.blessing in the DB) and an
+`intended blessing' (flights.intended). The `blessing' changes as the
+flight goes through the stages of its lifecycle. The `intended
+blessing' is roughly what the flight is going to be blessed as when
+its execution has completed, and controls host allocation.
+
+There is also the blessing which the flight will actually get when it
+is finished, which is not represented in the DB; rather, it is the
+blessing argument to sg-execute-flight (aka the -B argument to
+mg-execute-flight). Normally this is the same as the intended
+blessing in the DB, except for bisection flights.
+
+These are the principal (intended) blessings:
+
+ * `real': Flights which are fully production runs. They use only
+ clean working trees with no `funny' environment variables, and
+ versions of osstest intended for production. The data from such
+ flights is used, where applicable, to control production push gate
+ decisions, etc.
+
+ `blessed-real' hosts are fully production-ready.
+
+ * `play': Playground. Flights may use weird software, dirty working
+ trees, strange environment variables, and so on. It does not make
+ sense to point archaeology tools at such flights.
+
+ `blessed-play' hosts may be partially or completely nonfunctional,
+ or strange in some way. For this reason `play' flights should not
+ normally use the automatic host allocator.
+
+ * `adhoc': Special-purpose flights. They should be run with software
+ nearly as clean as `real': the version of the software used may not
+ be a branch intended for-production, but any enhancements or
+ modifications should not leave false or misleading information in
+ the history database.
+
+ `blessed-adhoc' hosts are just as good as `blessed-real' ones.
+
+ The `adhoc' blessing exists mostly to protect the main production
+ workflow from unintentional violations (for example, unexpectedly
+ buggy historical flight data).
+
+ * `commission-<something>': Flights used for testing that a
+ particular subset of the hosts are working properly. The hosts to
+ be tested should be blessed `commission-whatever' during
+ commissioning, and that blessing removed and replaced with `real'
+ when the hosts are ready.
+
+ * `real-bisect' and `adhoc-bisect': These are found only as the
+ blessing of finished flights. (This is achieved by passing
+ *-bisect to sg-execute-flight.) This allows the archaeologist
+ tools to distinguish full flights from bisection steps.
+
+ The corresponding intended blessing (as found in the `intended'
+ column of the flights table) is `real'. So the hosts used by the
+ automatic host allocator are those flagged `blessed-real' or
+ `blessed-adhoc' - there are no separate blessed-*-bisect hostflags.
+
+There are also blessings for unfinished flights:
+
+ * `constructing': The flight metadata (jobs, runvars, etc.) is still
+ being populated. The tools for flight construction (and flight
+ construct editing) generally insist that they operate only on
+ flights in this state.
+
+ * `running': At least one of the jobs in this flight has started.
+ Flight execution software will generally (perhaps via standard
+ library calls) mark a flight `running' if they find it
+ `constructing', and refuse to operate on other flights.
+
+ * `broken': Something went catastrophically wrong.
+
+ * `broken-*': Conventionally set by hand when a flight needs to be
+ `un-blessed', perhaps because it contains data misleading to the
+ archaeologists.
+
+ A flight's blessings can be manually changed with cs-flight-bless:
+ ./cs-flight-bless FLIGHT broken-real real
+ updates FLIGHT to be marked `broken' rather than `real'.
+ (cs-flight-bless matches the existing blessing against its final
+ argument, to avoid accidents.)
+
+Note that osstest is generally `crash-only software': nothing will
+`clean up' a crashed flight and set its blessing to `broken'. Flights
+which were in progress once upon a time but never completed, because
+they crashed, are simply left with whatever blessing they had at the
+time.
+
+There is a special exception to the tools' flight status checks: any
+flight whose blessing contains `play' can be operated on out of order.
Ian Campbell writes ("Re: [OSSTEST PATCH 1/9] README.dev: Document the blessings"): > On Thu, 2015-12-17 at 17:06 +0000, Ian Jackson wrote: > > +Each flight has a `blessing' and an `intended blessing'. The > > +`intended blessing' is what the flight is going to be blessed as when > > +its execution has completed. The intended blessing controls host > > +allocation. > > I think this could also usefully mention that `blessing' is the current > blessing, which may go through several phases during the life of the > flight, hopefully culminating in being set to `intended blessing' if the > flight is successful and that the archaeology tools only look at `blessing' > and never `intended blessing' Yes. > > +(Normally the `intended blessing' is the same as the bless argument to > > +sg-execute-flight aka the -B argument to mg-execute-flight.) > > How does this interact with the intended blessing passed to cs-flight- > create? So actually there a flight has three blessings. > > + * `real-bisect' and `adhoc-bisect': These are found only as the > > + blessing of finished flights. (This is achieved by passing *-adhoc > > + to sg-execute-flight.) This allows the archaeologist tools to > > + distinguish full flights from bisection steps. > > I don't follow the reference to *-adhoc here, since it matches neither > `real-bisect' nor `adhoc-bisect'. `Passing *-adhoc' should read `Passing *-bisect'. > > +There is a special exception to the tools' flight status checks: any > > +flight whose blessing contains `play' can be operated on out of order. > > + > > +Flights blessings can be manually changed with cs-flight-bless. Eg > > + ./cs-flight-bless FLIGHT broken-real real > > +updates FLIGHT to be marked `broken' rather than `real'. This can be > > The example says `broken-real' but the text says `broken' (if the text > didn't quote the `broken' it probably wouldn't matter. I have clarified this. > Maybe mention the need to pass the current blessing as a safety catch, > since it is part of the example command? Yes. squash! patch and complete v2, below. Ian. From 73903500006c0451cc81697872096fe2d6fe02ab Mon Sep 17 00:00:00 2001 From: Ian Jackson <ian.jackson@eu.citrix.com> Date: Thu, 17 Dec 2015 17:58:41 +0000 Subject: [OSSTEST PATCH] squash! README.dev: Document the blessings v2: Improvements from review --- README.dev | 39 ++++++++++++++++++++++++--------------- 1 file changed, 24 insertions(+), 15 deletions(-)