Top5 scalabilityissues withappendix
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The document discusses the top 5 things that hinder scalability: 1) monolithic design, 2) misidentification of shared resources, 3) overreliance on shared scopes, 4) stupid developer tricks like lazy pagination and query loops, and 5) failure to design for cacheability. It provides examples of each anti-pattern and potential solutions like partitioning databases, using SQL joins instead of queries in loops, encapsulating data access, and implementing caching at various layers from HTTP responses to databases.
![Example: Get Poll Answers
<cfset PollAnswers = entityLoad("PollAnswers",
{
PollID=entPoll[1].getPollID()
}, "")>
<cfif (isArray(Poll) AND arrayLen(Poll) GT 0)
AND (isArray(PollOpt)
AND arrayLen(PollOpt) GT 0)
AND (isArray(PollAnswers)
AND arrayLen(PollAnswers) GT 0)>](https://image.slidesharecdn.com/uqik81urtyiurvplb5xa-140515115728-phpapp01/85/Top5-scalabilityissues-withappendix-26-320.jpg)
![NoSQL as a Cache{
"_id" : ObjectId("51fff472e09a41ac19dd1876"),
"NAME" : "Dan",
"KIDS" : [
{
"NAME" : "Nick",
"AGE" : 2,
"HAIR" : "blonde"
},
{
"NAME" : "Jack",
"AGE" : 1,
"HAIR" : “none”,
}
]
}](https://image.slidesharecdn.com/uqik81urtyiurvplb5xa-140515115728-phpapp01/85/Top5-scalabilityissues-withappendix-40-320.jpg)
![A Note for MySQL users
[mysqld]
innodb_file_per_table
1. Do a mysqldump of all databases, procedures, triggers etc
except the mysql and performance_schema databases
2. Drop all databases except the above 2 databases
3. Stop mysql
4. Delete ibdata1 and ib_log files
5. Start mysql
6. Restore from dump](https://image.slidesharecdn.com/uqik81urtyiurvplb5xa-140515115728-phpapp01/85/Top5-scalabilityissues-withappendix-51-320.jpg)
![A Note for MySQL users
[mysqld]
innodb_file_per_table
1. Do a mysqldump of all databases, procedures, triggers etc
except the mysql and performance_schema databases
2. Drop all databases except the above 2 databases
3. Stop mysql
4. Delete ibdata1 and ib_log files
5. Start mysql
6. Restore from dump](https://image.slidesharecdn.com/uqik81urtyiurvplb5xa-140515115728-phpapp01/85/Top5-scalabilityissues-withappendix-52-320.jpg)
Top5 scalabilityissues withappendix
- 1. The Top 5 Things You are doing today to hinder scalability Dan Wilson
- 2. Who is Dan Wilson Runs ChallengeWave.com, Datacurl LLC and NCDevCon Technical Owner of Scholastic.com, Lead Architect of Forum Group Owner of Model-Glue Dad of 2, Husband to 1 Loves all things technical and a good debate
- 3. Our Top 5 List 1.Monolithic Design 2.Mis-identification/Misuse of shared resources 3.Over-reliance on Shared Scopes 4.Stupid Developer Tricks 5.Failure to design for cacheability
- 10. Fun With Math
- 11. Cost of WebServer File Web Server Thread + Network to File System + Disk Wait Time + Disk Seek Time + Transfer time to Webserver + Transfer time to complete HTTP Request ______________________ Total Time
- 12. Cost of 1 ColdFusion File Web Server Cost + Network Cost to CF Server + CF Parsing or Classloading Time + Thread Wait time + Thread CPU time + Transfer time for CF buffer to Webserver ______________________ Total Time
- 13. Cost of ColdFusion File With Query Web Server Cost + ColdFusion File Cost + Number of Queries ( Network time to DB + Query Execution Plan + Query Execution + Disk Wait + Disk Seek ) + Network time to transport result set to CF + CF Parsing Time ______________________ Total Time
- 14. Types of Shared Resources ● Memory, CPU, Disk Space ● Disk Transfer (Databases!!) ● JVM Space ● ColdFusion template cache ● ColdFusion Threads ● Network Traffic ● Database
- 15. DANGER! DANGER!
- 16. Over-reliance on Shared Scopes ● Session Scope use is the largest culprit ● Sometimes you have to deoptimize a few operations in order to provide a scalable solution (like stop caching a state query in application) ● If you want to use a shared scope and want to keep an eye on scalability later, use a lookup factory.
- 17. <cfcomponent> <cfset variables.instance = structNew() /> <cffunction name="init" returntype="CurrentUserLoader" output="false" access="public"> <cfargument name="Transfer" type="any" required="true"/> <cfset variables.transfer = arguments.transfer /> <cfreturn this /> </cffunction> <cffunction name="destroy" output="false" access="public" returntype="void" > <cfset cookie.userID = "" /> <cfset structDelete( cookie, "userID") /> </cffunction> <cffunction name="load" output="false" access="public" returntype="any" hint=""> <cfset var loggedInUserID = 0 /> <cfif structkeyExists(cookie, "userID")> <cfset loggedInUserID = cookie.userID /> </cfif> <cfreturn variables.transfer.get("User", val( loggedInUserID ) ) /> </cffunction> <cffunction name="set" output="false" access="public" returntype="void" hint=""> <cfargument name="user" type="any" required="true"/> <cfset cookie.UserID = arguments.User.getUserID() /> <cfset cookie.Email = arguments.User.getEmail() /> </cffunction> </cfcomponent>
- 18. Avoiding Server Shared Scopes
- 19. Stupid Developer Tricks ● Looped Queries ● Lazy-Man Pagination ● ScheduledTask-o-rama ● Database Abuse
- 20. Problem: Query in Loop <cfloop query="OldLastLogins"> <cfquery name="UpdateUsers" datasource="#datasource#"> UPDATE Users SET Active = 0 WHERE UserID = #OldLastLogins.UserID# </cfquery> </cfloop>
- 21. Solution?: SQL IN Statement <cfquery name="UpdateUsers" datasource="#datasource#"> UPDATE Users SET Active = 0 WHERE UserID IN #ValueList(OldLastLogins, UserID)# </cfquery>
- 23. Solution: Joins <cfquery name="UpdateUsers" datasource="#datasource#"> UPDATE users INNER JOIN lastlogin ON users.userID = lastlogin.userID SET Active = 0 WHERE lastlogin < now() </cfquery>
- 24. Solution: Joins <cfquery name="UpdateUsers" datasource="#datasource#"> UPDATE users INNER JOIN lastlogin ON users.userID = lastlogin.userID SET users.lastLoginDate = lastlogin.createdDate WHERE lastlogin < now() </cfquery>
- 25. Problem: EntityToQuery <cfscript> EntityToQuery( EntityLoad("Users", { Gender = arguments.genderID} ) ); </cfscript>
- 26. Example: Get Poll Answers <cfset PollAnswers = entityLoad("PollAnswers", { PollID=entPoll[1].getPollID() }, "")> <cfif (isArray(Poll) AND arrayLen(Poll) GT 0) AND (isArray(PollOpt) AND arrayLen(PollOpt) GT 0) AND (isArray(PollAnswers) AND arrayLen(PollAnswers) GT 0)>
- 27. Poll Net Result JDBC Recordcount: 87,923 Query Time: 14,290 ms All that for an ArrayLen() GT 0!
- 28. Solution: Query <cfquery name="LoadGenderUsers" datasource="#datasource#"> SELECT UserID, UserName, Email, GenderID FROM Users WHERE GenderID = '#arguments.GenderID#' </cfquery>
- 29. Problem: Lazy Man Pagination <cfoutput query="GetParks" startrow="#StartRow#" maxrows="#MaxRows#"> #ParkName# </cfoutput>
- 30. Solution: SQL MySql, PostgreSQL: LIMIT, OFFSET SQL Server: TOP, ORDER BY ORACLE: WHERE rownum <= 10
- 31. Problem: No Encapsulation <cfif qExists.idexists> <cfquery name="qUpdate" datasource="#somedatasource#"> UPDATE tblKalendarCategories SET CategoryName = '#form.CategoryName#', CategoryTextColor = '#form.CategoryTextColor#' WHERE CategoryID = #form.CategoryID#' /> </cfquery> <cfelse> <cfquery name="qCreate" datasource="#somedatasource#"> INSERT INTO tblKalendarCategories ( CategoryName, CategoryBGColor, CategoryTextColor ) VALUES ( '#form.CategoryName#', '#form.CategoryTextColor#') </cfquery> </cfif>
- 32. Solution: Encapsulate Data Access DAO.read(); DAO.delete(); DAO.exists(); DAO.save(); DAO.create(); DAO.update();
- 33. Bad or No Indexing
- 34. Cacheability
- 35. Caching Layers
- 36. Caching HTTP Responses Request: GET /index.html HTTP/1.1 Host: www.example.com Response: HTTP/1.1 200 OK Date: Mon, 23 May 2005 22:38:34 GMT Server: Apache/1.3.3.7 (Unix) (Red- Hat/Linux) Last-Modified: Wed, 08 Jan 2003 23:11:55 GMT ETag: "3f80f-1b6-3e1cb03b" Content-Type: text/html; charset=UTF-8 Content-Length: 131 Accept-Ranges: bytes Connection: close
- 38. Designing for a CDN or Reverse Proxy Cache ● Use HTTP verb “GET” for cacheable content ● Use Last-Modified and Etag headers properly ● Encapsulate code that changes content to centralize cache purge activity ● Personalize with Cookies/Javascript ● Set up shadow DNS to bypass caching ● Use Javascript for interactions ● Design data for high cache hit ratios
- 39. Caching Data
- 40. NoSQL as a Cache{ "_id" : ObjectId("51fff472e09a41ac19dd1876"), "NAME" : "Dan", "KIDS" : [ { "NAME" : "Nick", "AGE" : 2, "HAIR" : "blonde" }, { "NAME" : "Jack", "AGE" : 1, "HAIR" : “none”, } ] }
- 42. Designing for a NoSQL Cache ● Encapsulate calls to NoSQL engine ● Encapsulate data publish methods ● Design Content Purge algorithms well ● Ensure the NoSQL engine is the authoritative source for the data being stored
- 43. Key/Value stores
- 44. Key Value Store Cache Diagram
- 45. Designing for a Key Value Store Cache ● Encapsulate data access calls so you can purge/reload ● Avoid cffunction output=”true” ● Choose correct cache expiry strategy (time, LRU) ● Easy to integrate with CF ORM ● Use to remove load hotspoting
- 46. <cfcomponent> <cffunction name="loadProduct" returntype="Product" access="public"> <cfargument name="ProductID" type="numeric" required="true"/> <cfset var CacheKey = makeProductCacheKey(arguments.ProductID)/> <cfif variables.Cache.exists(CacheKey) IS false> <cflock name="#CacheKey#" timeout="10"> <cfif variables.Cache.exists(CacheKey) IS false> <cfset variables.Cache.put(CacheKey, variables.ProductService.get(arguments.ProductID))/> </cfif> </cflock> </cfif> <cfreturn variables.Cache.get(CacheKey)/> </cffunction> <cffunction name="saveProduct" returntype="Product" access="public"> <cfargument name="ProductID" type="numeric" required="true"/> <cfargument name="Name" type="text" required="true"/> <cfset var CacheKey = makeProductCacheKey(arguments.ProductID)/> <cfset var Product = variables.ProductService.get(arguments.ProductID)/> <cfset Product.setName(arguments.Name)/> <cfset Product = variables.ProductService.save(Product)/> <cfset variables.Cache.set(CacheKey, Product)/> <cfreturn variables.Cache.get(CacheKey)/> </cffunction> <cffunction name="makeProductCacheKey" returntype="string" access="private"> <cfargument name="ProductID" type="numeric" required="true"/> <cfreturn "Product_#val(arguments.ProductID)#"/> </cffunction> </cfcomponent>
- 48. Time is Money
- 50. Appendix and helpful links
- 51. A Note for MySQL users [mysqld] innodb_file_per_table 1. Do a mysqldump of all databases, procedures, triggers etc except the mysql and performance_schema databases 2. Drop all databases except the above 2 databases 3. Stop mysql 4. Delete ibdata1 and ib_log files 5. Start mysql 6. Restore from dump
- 52. A Note for MySQL users [mysqld] innodb_file_per_table 1. Do a mysqldump of all databases, procedures, triggers etc except the mysql and performance_schema databases 2. Drop all databases except the above 2 databases 3. Stop mysql 4. Delete ibdata1 and ib_log files 5. Start mysql 6. Restore from dump
- 53. Content Delivery Network PROS ● Caches HTTP Response ● Ajax Friendly ● Static Content ● TTL/Manual Purge ● Blazing Fast ● Can be geographically distributed ● No physical infrastructure to manage ● Pay for what you use CONS ● Pay for what you use ● SSL is more complicated ● Testing is more complicated ● Reliant on external service ● Not a good fit for intranet traffic
- 55. Monitoring Options ColdFusion Server Monitor CFStat New Relic – SaaS Fusion Reactor Monitor Nagios
- 56. Reverse Proxy Cache (Front Cache)
- 57. Reverse Proxy Cache PROS ● Caches HTTP Response ● Ajax Friendly ● Static Content ● TTL/Manual Purge ● Blazing Fast ● Many Open Source Products ● Low operating expense ● Can be used for intranets CONS ● Personalization must be client side (no session scope) ● Content is treated as static ● Testing is more complicated ● Must Manage Physical Infrastructure ● Often Geographically Localized
- 58. Key Value Store PROS ● Blazing Fast ● Can cache any in- memory item ● Some caches are sophisticated, some aren't ● Can be distributed ● Simple interfaces ● Integrated in CF CONS ● Many Cached Items represent an HTTP request ● What is real-time to your application? ● Key management can be hard ● WYCIWYG (what you cache is what you get)
- 59. Helpful Links In-Memory Cache http://www.ehcache.org http://terracotta.org/coldfusion http://memcached.org Reverse Proxy Cache http://varnish-cache.org http://www.squid-cache.org http://trafficserver.apache.org Tutorials on Caching Varnish: http://bit.ly/c1puD6 Squid Video: http://bit.ly/9iZu1Z Aaron West: http://bit.ly/a4sYcr Rob Brooks-Bilson: http://bit.ly/txser Terracotta Webinar: http://www.terracotta.org/webcasts This presentation: http://tinyurl.com/cacheme Scalability Blogs http://cfwhisperer.com http://highscalability.com