redis präsentation

1. Redis

2. Wer benutzt Redis?

3. Instagram
• Redis powers their main feed, activity
feed, sessions system.
• Redis runs on several Quadruple
Extra-Large Memory instances.
• runs in a master-replica setup. Replicas
constantly save to disk.

4. Stackoverflow
• Use Redis as a caching layer for the
entire network.
• around 1.300.000 keys in Redis cache.
• peak time we're getting a few hundred
read/writes a second to Redis.
• about 1% cpu usage
• started storing much bigger things in
Redis, like inboxes

5. Redis
• Schlüssel-Werte Datenstruktur
• In-Memory-Datenbank
• Transaction (optimistic Locking)
• Kein MapReduce

6. Philosophie
Performance
100.000 Schreiboperation
80.000 Leseoperation
pro Sekunde

7. Datenstrukturen
• String
• Hashes
• Lists
• Sets
• Sorted Sets

8. String
SET mykey "Hello"
GET mykey

9. Hash
HSET myhash field1 "Hello"
HGET myhash field1

10. Sets
SADD myset "Hello"
SADD myset "World"
SMEMBERS myset

11. Sorted Sets
ZADD myzset 1 "one"
ZADD myzset 1 "uno"
ZADD myzset 2 "two"
ZRANGE myzset 0 -1 WITHSCORES

12. Praktikum

13. Abfrage
Alle Buchungen, bei denen der Flug in
Düsseldorf (DUS) begonnen wird.

15. modelleriung
java
feingranular

16. Datenstruktur Schlüssel Wert
Set bookings
00QKXC
00D3N0
String exposed:00QKXC 0
Set passengers:00QKXC
Anna:Becker
Alexander:Becker
Hash Anna:Becker
salutations => MS
firstname => Anna
lastname => Becker
List flights:00QKXC
flight:TG921
flight:TG920
Hash flight:TG921
date => 1373407200
departs => 1373460300
fromAirportAbbr => DUS
Hash service:TG921 Infant
Hash seats:TG921
RAUSS/ARMINMR => 08C
(Non-smoking)
Hash fares:00QKXC
type => ADT
taxes => 57.22
Set segments:00QKXC
1
2

17. Realisierung
Set<String> allBookingIds = jedis.smembers(BOOKINGS);
String flightId;
for(String bookingId : allBookingIds) {
flightId = jedis.lrange(FLIGHTS + bookingId, 0, 0).get(0);
if(jedis.hget(flightId, FROM_AIRPORT_ABBR).equals(startAirport)){
allBookings.add(getBooking(bookingId));
}
}

18. modelleriung
java
grobgranular

19. ticket:00P5LM:eticket:220327240100C1,220327240100C2:exposed:1:flights:DUS->CDG->CDG->DUS
Hash Name
key => flights
flights => {...........}
Datenstruktur

20. GUI-Client

21. Realisierung
function getBookingsStartingIn($redis, $airport)
{
echo "----------------------------------------------------------n";
echo "Flüge die in $airport starten:n";
$tickets = $redis->query("*flights:$airport->*");
foreach ($tickets as $ticket){
echo "Flight " . $ticket["id"] . " starts in $airportn";
}
echo "----------------------------------------------------------n";
}

23. Fazit
• Einfache und schnelle Abfragen sind mit
Redis sehr gut zu realisieren.
• Gute Dokumentation.
• Abfragesprache ist nicht mächtig.

24. Danke für die
Aufmerksamkeit

25. Links
• Praktikum (Wiki)
• Installation (Webseite)
• Redis Befehle (API)
• NoSQL Einführung (Buch)
• Seven Databases in Seven Weeks (Buch)