v8/tools/testrunner/testproc/shard.py
Tamer Tas ad5b6d7dcb [testrunner] enable variant sharding
Testrunner runs variants of a test sequentially without taking sharding into
account. A slow test with slow variants slows down the whole test run no matter
the sharding configuration.

This CL implements a test hashing algorithm and variant sharding for test
variants.

R=machenbach@chromium.org
CC=yangguo@chromium.org,sergiyb@chromium.org

Bug: v8:8174
Change-Id: I15f8c547fa2f361fb6c53bf8d5df055d3df38d3e
Reviewed-on: https://chromium-review.googlesource.com/c/1458016
Commit-Queue: Tamer Tas <tmrts@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59530}
2019-02-12 13:40:33 +00:00

39 lines
1.0 KiB
Python

# Copyright 2018 the V8 project authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
from . import base
# Alphabet size determines the hashing radix. Choosing a prime number prevents
# clustering of the hashes.
HASHING_ALPHABET_SIZE = 2 ** 7 -1
def radix_hash(capacity, key):
h = 0
for character in key:
h = (h * HASHING_ALPHABET_SIZE + ord(character)) % capacity
return h
class ShardProc(base.TestProcFilter):
"""Processor distributing tests between shards.
It hashes the unique test identifiers uses the hash to shard tests.
"""
def __init__(self, myid, shards_count):
"""
Args:
myid: id of the shard within [0; shards_count - 1]
shards_count: number of shards
"""
super(ShardProc, self).__init__()
assert myid >= 0 and myid < shards_count
self._myid = myid
self._shards_count = shards_count
def _filter(self, test):
return self._myid != radix_hash(self._shards_count, test.procid)