Use factored-out BuildResult serializer

For the record, here is the Nix 2.19 version:
https://github.com/NixOS/nix/blob/2.19-maintenance/src/libstore/serve-protocol.cc,
which is what we would initially use.

It is a more complete version of what Hydra has today except for one
thing: it always unconditionally sets the start/stop times.

I think that is correct at the other end seems to unconditionally
measure them, but just to be extra careful, I reproduced the old
behavior of falling back on Hydra's own measurements if `startTime` is
0.

The only difference is that the fallback `stopTime` is now measured from
after the entire `BuildResult` is transferred over the wire, but I think
that should be negligible if it is measurable at all. (And remember,
this is fallback case I already suspect is dead code.)
This commit is contained in:
John Ericson 2023-12-07 02:00:22 -05:00
parent a5d44b60ea
commit 6a54ab24e2

View file

@ -286,9 +286,6 @@ static BuildResult performBuild(
counter & nrStepsBuilding
)
{
BuildResult result;
conn.to << ServeProto::Command::BuildDerivation << localStore.printStorePath(drvPath);
writeDerivation(conn.to, localStore, drv);
conn.to << options.maxSilentTime << options.buildTimeout;
@ -301,30 +298,25 @@ static BuildResult performBuild(
}
conn.to.flush();
result.startTime = time(0);
BuildResult result;
time_t startTime, stopTime;
startTime = time(0);
{
MaintainCount<counter> mc(nrStepsBuilding);
result.status = (BuildResult::Status)readInt(conn.from);
result = ServeProto::Serialise<BuildResult>::read(localStore, conn);
}
result.stopTime = time(0);
stopTime = time(0);
result.errorMsg = readString(conn.from);
if (GET_PROTOCOL_MINOR(conn.remoteVersion) >= 3) {
result.timesBuilt = readInt(conn.from);
result.isNonDeterministic = readInt(conn.from);
auto start = readInt(conn.from);
auto stop = readInt(conn.from);
if (start && start) {
/* Note: this represents the duration of a single
round, rather than all rounds. */
result.startTime = start;
result.stopTime = stop;
}
}
if (GET_PROTOCOL_MINOR(conn.remoteVersion) >= 6) {
ServeProto::Serialise<DrvOutputs>::read(localStore, conn);
if (!result.startTime) {
// If the builder gave `startTime = 0`, use our measurements
// instead of the builder's.
//
// Note: this represents the duration of a single round, rather
// than all rounds.
result.startTime = startTime;
result.stopTime = stopTime;
}
return result;