Files
scylladb/encoding_stats.hh
2018-05-04 15:45:10 -07:00

53 lines
2.1 KiB
C++

/*
* Copyright (C) 2018 ScyllaDB
*/
/*
* This file is part of Scylla.
*
* Scylla is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Scylla is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Scylla. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include "timestamp.hh"
// Stores statistics on all the updates done to a memtable
// The collected statistics are used for flushing memtable to the disk
struct encoding_stats {
// The fixed epoch corresponds to the one used by Origin - 22/09/2015, 00:00:00, GMT-0:
// Calendar c = Calendar.getInstance(TimeZone.getTimeZone("GMT-0"), Locale.US);
// c.set(Calendar.YEAR, 2015);
// c.set(Calendar.MONTH, Calendar.SEPTEMBER);
// c.set(Calendar.DAY_OF_MONTH, 22);
// c.set(Calendar.HOUR_OF_DAY, 0);
// c.set(Calendar.MINUTE, 0);
// c.set(Calendar.SECOND, 0);
// c.set(Calendar.MILLISECOND, 0);
//
// long TIMESTAMP_EPOCH = c.getTimeInMillis() * 1000; // timestamps should be in microseconds by convention
// int DELETION_TIME_EPOCH = (int)(c.getTimeInMillis() / 1000); // local deletion times are in seconds
// Encoding stats are used for delta-encoding, so we want some default values
// that are just good enough so we take some recent date in the past
static constexpr uint32_t deletion_time_epoch = 1442880000;
static constexpr api::timestamp_type timestamp_epoch = api::timestamp_type(deletion_time_epoch) * 1000 * 1000;
static constexpr uint32_t ttl_epoch = 0;
api::timestamp_type min_timestamp = timestamp_epoch;
uint32_t min_local_deletion_time = deletion_time_epoch;
uint32_t min_ttl = ttl_epoch;
};