1.
6.1. SaaS<br />34330<br />EEDC<br />Execution<br />Environments for <br />Distributed <br />Computing<br />6.1.1. What’s SaaS<br />6.1.2. Multi-Tenancy<br />6.1.3. Batch processing<br />Master in Computer Architecture, Networks and Systems - CANS<br />

2.
6.1. SaaS<br />34330<br />EEDC<br />Execution<br />Environments for <br />Distributed <br />Computing<br />6.1.1. What’s SaaS<br />6.1.2. Multi-Tenancy?<br />6.1.3. Batch processing<br />Master in Computer Architecture, Networks and Systems - CANS<br />

3.
What’s Software as a Service?<br />

4.
WhySaaS?. On PremisesCashFlow<br />Crisis!<br />Customization & Deploy<br />New project<br />

5.
Título de la presentación<br />WhySaaS?. SaaSCashFlow<br />Crisis!<br />New customer<br />Actual customers<br />

6.
6.1. SaaS<br />34330<br />EEDC<br />Execution<br />Environments for <br />Distributed <br />Computing<br />6.1.1. What’s SaaS<br />6.1.2. Multi-Tenancy?<br />6.1.3. Batch processing<br />Master in Computer Architecture, Networks and Systems - CANS<br />

7.
What’s Multi-Tenancy?<br />You DON’T have a 1:1 relationbetweencustomers and instances of data<br />

8.
SaaS ERP<br />Multi-Tenancy @ Spain targeting non-technological SMB (PyMEs)?<br />NO way!<br />Cultural issues were (and are) impacting their bottom-line and single-tenancy at database allows them to send backups of data to their customers as a «peace of mind»<br />They faced a trade-off between less scalability and bigger infrastructure costs, and selling to THEIR customers and easier development<br />

9.
SaaS ERP<br />1st boxed software, on premises deploy & customization, remote upgrades, support, etc..<br />2nd Dual offering, boxed to big/special customers and SaaS using the same code base to smaller customers -> saving on support and upgrades<br />3rd Re-engineering of code to allow better concurrency. Developing their own RDP load balancer and a runtime to improve developing software (Visual Basic to C#.Net)<br />

10.
SaaS ERP: Re-engineering<br />Problems:<br />Low concurrency level<br />One user could affect all user on this server<br />Peaks at month end (billing, payroll,…)<br />Printing<br />Licenses cost (Citrix, Terminal Server, Windows, SQL Server)<br />

11.
SaaS ERP: Re-engineering<br />Solutions:<br />3 tier model (client, application server, database)<br />Client only renders, all calculations at server side<br />Same client and application server for all customers<br />Most reports go to printer so speed isn’t important, let’s shape the demand<br />Leverage asynchronous calls between client and server<br />Found tool to get rid of those printer drivers at the Terminal server<br />Developed a tool with instrumentation to substitute Citrix licenses<br />Has to be single-tenant at database side<br />

12.
SaaS ERP: Single-Tenant<br />Single-Tenant at databaselevel<br />

13.
6.1. SaaS<br />34330<br />EEDC<br />Execution<br />Environments for <br />Distributed <br />Computing<br />6.1.1. What’s SaaS<br />6.1.2. Multi-Tenancy?<br />6.1.3. Batch processing<br />Master in Computer Architecture, Networks and Systems - CANS<br />

14.
Batch processing only for Research?<br />What’s Batch processing?<br />Wait to have a bunch of things to process<br />Launch process to do things that last some time<br />Get the results after non trivial time<br />Why Batch processing?<br />Better Throughput at Latency expenses<br />

15.
Batch processing only for Research?<br />What’s Batch processing?<br />Wait to have a bunch of things to process<br />Launch process to do things that last some time<br />Get the results after non trivial time<br />Why Batch processing?<br />Better Throughput at Latency expenses<br />

16.
Sending newsletters<br />What a newsletter app looks like?<br />

17.
Batch vs. Online<br />Where we don’t need hard real-time<br />

18.
Batch optimization<br />If we wait enough…<br />We’ll have enough e-mails to same server to leverage<br />SMTP Pipelining<br />TCP Slow Start. Typical email 30 KB, BW 100 mb/s = 2 ms/email, but RTT 200 ms<br />

19.
Batch optimization<br />If we wait enough…<br />We’ll have other problems<br />File System, too many files at the same folder<br />Time to read/create file O(n) on most file systems<br />Spool has to be persistent so we have to much write IOPS<br />Leverage hashing again<br />Hash files to folders so: 12132324.queue -> ab/c3/12132324.queue<br />Enable write back cache at the storage device<br />

20.
Batch optimization<br />If we wait enough…<br />Went from 5.000 emails/hour <br />to 500.000 emails/hour<br />And save money as senders only need to be up when they are doing something (API to IaaS provider)<br />

21.
Reporting optimization<br />Every click or image went to an Apache Server<br />Look for URL to redirect<br />Insert to access MySQL<br />Reporting using real-time aggregation queries<br />

22.
Reporting optimization<br />Using a CDN + log parsing + Hive + Hbase we can escalate reporting<br />As the CDN doesn’t cache HTTP redirects we enable a poll based server sending redirects and logging the access<br />Urls looks like: http://esp.net/customer_id/link_id/mail_id<br />Also is easy to escalate with a simple load balancer<br />

23.
Aboutthissession<br />34330 Execution Environments for Distributed Computing (EEDC), Master in Computer Architecture, Networks and Systems (CANS) Computer Architectura Department (AC)<br />UniversitatPolitècnica de Catalunya – Barcelona Tech (UPC)<br />INSTRUCTOR<br />Sergi Morales, Founder & CTO of Expertos en TIPhone: +34 6688-XPNTIEmail : sergi.morales+eedc@expertosenti.comBlog : http://blog.expertosenti.com<br /> Web: http://www.expertosenti.com<br />

24.
About the EEDC course <br />34330 Execution Environments for Distributed Computing (EEDC), Master in Computer Architecture, Networks and Systems (CANS) Computer Architectura Department (AC)<br /> Universitat Politècnica de Catalunya – Barcelona Tech (UPC) ECTS credits: 6<br />INSTRUCTOR<br /> Professor Jordi TorresPhone: +34 93 401 7223 Email : torres@ac.upc.eduOffice : Campus Nord, Modul C6. Room 217.<br /> Web: http://www.JordiTorres.org<br />

25.
34330<br />EEDC<br />Execution<br />Environments for <br />Distributed <br />Computing<br />Sergi Morales<br />Founder & CTO<br />T: 668897684<br />E: sergi.morales@expertosenti.com<br />L: www.linkedin.com/in/sergimorales<br />Master in Computer Architecture, Networks and Systems - CANS<br />

26.
Case<br />Asynchronous access to Facebook API server<br />Expect to fail<br />Tables with so many rows, a key/value approach<br />Consistent hashing to loadbalance data<br />Sticky servers?<br />