a310901280
We did a small experiment to see how a full scan of the Redis keys on gitlab.com speeds up as we increase the batch size. The values on the right are time in seconds for a full scan (no delete operations). count: 10); 284.500529021 count: 100); 86.21216934 count: 1_000); 60.931676195 count: 10_000); 60.96355610 count: 100_000); 62.378172541 It looks like 1,000 is a good number.
21 lines
616 B
Ruby
21 lines
616 B
Ruby
namespace :cache do
|
|
CLEAR_BATCH_SIZE = 1000 # There seems to be no speedup when pushing beyond 1,000
|
|
REDIS_SCAN_START_STOP = '0' # Magic value, see http://redis.io/commands/scan
|
|
|
|
desc "GitLab | Clear redis cache"
|
|
task :clear => :environment do
|
|
redis_store = Rails.cache.instance_variable_get(:@data)
|
|
cursor = REDIS_SCAN_START_STOP
|
|
loop do
|
|
cursor, keys = redis_store.scan(
|
|
cursor,
|
|
match: "#{Gitlab::REDIS_CACHE_NAMESPACE}*",
|
|
count: CLEAR_BATCH_SIZE
|
|
)
|
|
|
|
redis_store.del(*keys) if keys.any?
|
|
|
|
break if cursor == REDIS_SCAN_START_STOP
|
|
end
|
|
end
|
|
end
|