DEV31 Designing your ABL Application for Performance tips

DEV-31: Designing your ABL Application for Performance tips and tricks Peter Judge Principal Software Engineer

Wherefore art thou, performance? § § As important as stability, features, quality Affected by • Changing user counts, data, activity, traffic • Application design & programming techniques § § Different functionality = different needs What determines good performance? • Using the available resources efficiently § Better performance improves user satisfaction “I know it when I see it” US Supreme Court Justice Potter Stewart 2 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

What can I do about it? § Hardware faster, cheaper over time • Software upgrades vs. hardware upgrades Does faster hardware make you lazy? § You can only change what you control • System configuration § Design & code for performance • Don’t go overboard • Don’t make things worse § Test & measure 3 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Agenda § Coding for performance § Testing & measurement § Deployment & runtime considerations

Coding design § Good design is necessary • Can have performance cost • Classes generally faster than procedures • Consider caching § “Warehouse” into Pro. Data. Sets for reporting • Don’t try to do it all with one FOR EACH 5 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Green coding § The fastest code is no code at all § Clean up after yourself • Manage widgets using WIDGET-POOL • Store references for deletion § Define statically, access dynamically • Reuse what you can § Only get the data you need • Filtered data for UI 6 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Data across the network § Network typically major bottleneck § Number of roundtrips • Making App. Server connection has cost § Data volume per roundtrip Num trips • Makes other performance problems worse Data per trip § Network topography has impact … … but usually out of our control 7 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Optimize network roundtrips login. Window. w 1 run get. Login. Languages() run get. Login. Companies() 2 run build. UI(). 8 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Optimize network roundtrips login. Window. w run get. UIData() 1 run build. UI(). 9 DEV-31: Designing your ABL Application for Performance get. Ui. Data() run get. Login. Languages() run get. Login. Companies() © 2008 Progress Software Corporation

Reduce data volume § Put your temp-tables on a diet • Use MIN-SCHEMA-MARSHAL or NO-SCHEMAMARSHAL – Stay away from RCODE-INFO • Use transport temp-tables • Use enumerations to compress data § Compression • -mc (message compression) • -mm (message buffer size) 10 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

No deep copies define temp-table tt. Data. . . run run populate. Data (output table tt. Data). visualise. Data (input table tt. Data). get. Changes (output table tt. Data). save. Changes (input table tt. Data). define temp-table tt. Data. . . h = buffer tt. Data: handle. run run 11 populate. Data (output h). visualise. Data (input h). get. Changes (output h). save. Changes (input h). DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

No deep copies (2) define temp-table tt. Data. . . run run populate. Data (output table tt. Data). visualise. Data (input table tt. Data). get. Changes (output table tt. Data). save. Changes (input table tt. Data). define temp-table tt. Data. . . run run 12 populate. Data (output table tt. Data by-reference). visualise. Data (input table tt. Data by-reference). get. Changes (output table tt. Data by-reference). save. Changes (input table tt. Data by-reference). DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Evaluate functions as rarely as possible 13 do i = 1 to udf. Get. Num. Iter(): end. j = udf. Get. Num. Iter(). do i = 1 to j: end. do i = 1 to num-entries(c. Lst): end. j = num-entries(c. Lst). do i = 1 to j: end. do i = 1 to 10: j = udf. Get. Max. Value(). /* do something with j */ end. j = udf. Get. Max. Value(). do i = 1 to 10: /* do something with j */ end. DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

CASE faster than nested IF If c. Alpha = “A” then. . . else if c. Alpha = “B” then. . . else if c. Alpha = “C” then. . . else. . . case c. Alpha: when “A” then. . . when “B” then. . . when “C” then. . . otherwise. . . end case. 14 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Arrays faster than delimited lists c. Delim = “, ”. /* or CHR(3) or | or. . . */ c. List = “item 1” + c. Delim + “item 2” + c. Delim +. . . + “item. N”. do i = 1 to num-entries(c. List, c. Delim): c. Entry = entry(i, c. List, c. Delim). c. Array[1] = “item 1”. c. Array[2] = “item 2”. c. Array[n] = “item. N”. do i = 1 to extent(c. Array): /* do stuff with */ c. Array[i] 15 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Always use NO-UNDO define variable c. Var for char no-undo. def public property Access. Time as datetime no-undo get. set. define input parameter pi. Param as int no-undo. define temp-table tt. Data no-undo field index. Field as character field data. Field as decimal. 16 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Group your ASSIGNments c. Var = “abc”. i. Var = 123. dt. Var = now. tt. Data. index. Field = “Pi”. tt. Data. data. Field = get. Pi. Val(). assign c. Var = “abc” i. Var = 123 dt. Var = now tt. Data. index. Field = “Pi” tt. Data. data. Field = get. Pi. Val(). 17 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Blocks repeat i = 1 to 10: do i = 1 to 10: end. if condition 1 then do: c. Var = c. Value. c. Time = now. end. if condition 1 then assign c. Var = c. Value c. Time = now. § function, procedure, method all blocks • Inline code may be faster – Use includes for code re-use 18 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Combining techniques j = extent(c. Array). do i = 1 to j: c. Array[i] = c. Array 2[i]. end. j = extent(c. Array). n = 50. /* depends on data distribution */ do i = 1 to j by n: assign c. Array[i] = c. Array 2[i] c. Array[i+1] = c. Array 2[i+1]. . . c. Array[i+n] = c. Array 2[i+n]. end. 19 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Error handling do on error undo, return error ‘oops’: o = new App. Module. Class(). o: Method 1(). o: Method 2(). end. do on error undo, return error ‘oops’: o = new App. Module. Class(). o: Method 1(). o: Method 2(). /* Some Other Stuff Happens */ catch e as Progress. Lang. Error: undo, throw new Progress. Lang. Error (‘oops’). end catch. end. 20 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Error handling (2) run method 1 in hdl () no-error. if error-status: error then return error return-value. run method 2 in hdl () no-error. if error-status: error then return error return-value run method 1 in hdl(). run method 2 in hdl(). catch e as Progress. Lang. Error: undo, throw e. /* alternatively, throw a new, different error */ undo, throw new Progress. Lang. Error (‘oops’). end catch. 21 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Loop hoisting do i = 1 to n: if condition 1 then do: /* stuff */ end. else if condition 2 then do: /* more stuff */ end. else do: /* other stuff */ end. 22 DEV-31: Designing your ABL Application for Performance if condition 1 then do i = 1 to n: /* stuff */ end. else if condition 2 then do i = 1 to n: /* more stuff */ end. else do i = 1 to n: /* other stuff */ end. © 2008 Progress Software Corporation

Class properties class App. Module. Exchange. Venue: def public property City. Name as char no-undo get. set. def public property City. Location as char no-undo get (): /* gets lat/long of city as string from Web. Service */ end get. set. end class. o = new App. Module. Object(). o: City. Name = “Paris”. c. Loc 23 = o: City. Location. DEV-31: Designing your ABL Application for Performance Effectively an ASSIGN Effectively a function invocation © 2008 Progress Software Corporation

Sequences find counters where counters. seq_name = “cust_num” exclusive-lock no-wait no-error. /* check lock & wait status; act accordingly */ create customer. assign customer. cust-num = counters. value + 1. . . create customer. assign customer. cust-num = next-value(seq_cust_num). . . 24 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Unique values (when order doesn’t matter) create customer. assign customer. id = string(next-value(seq_table_id), “ 9999999”). . . create customer. assign customer. id = guid(). . . 25 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Understand how indexes work § Understand index selection rules • Take care with OR in WHERE clause • Also BY clause § Confirm actual indexes used • COMPILE. . . XREF • INDEX-INFORMATION attribute 26 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Know your indexes § Only maintain the indexes you need • Add more indexes • Get rid of unused indexes § Multi-component indexes are good § Unique indexes faster than non-unique § ROWID access is very fast 27 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Efficient data access § Join from smallest bracket to largest • Not always parent to child e. g. Date ranges for each Customer where credit-limit >= 100, each Order of Customer where order-date = today: /* create report */ Customer 1 0. . * Order for each Order where order-date = today, first Customer of Order where credit-limit >= 100: /* create report */ 28 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Dealing with LOGICAL and status values for each Employee where gender = “Male” and /* or Female */ emp-status = “Perm” and /* or Contract */ currently-employed = true /* or false */ c. Status = “Male” + “|” + “Perm” + “|” + “Cur. Emp”. for each Employee where status contains c. Status: for each Status where status = “Perm” or status = “Male” or status = “Cur. Emp”, each Emp. Status of Status, each Employee of Emp. Status: 29 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Avoid un-indexed CAN-FIND if can-find(first Customer where name matches “*Jon*”) then. . . if can-find(first Customer where name contains “Jon”) then. . . if can-find(first Customer where name begins “Jon”) then. . . 30 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Avoid conditional WHERE clause processing for each Customer where (if i. Cust. Num > 0 then cust-num = i. Cust. Num else true). define query qry. Cust for Customer. if i. Cust. Num > 0 then open query qry. Cust for each Customer where cust-num = i. Cust. Num. else open query qry. Cust for each Customer. 31 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Testing for performance § Measure performance • The only way to know for sure • Measure more than once • Measure against predefined goals § Use regression test suite • Use constant, realistic environments • Compare against baselines • Automate as far as possible § Ongoing, iterative process • Engineers’ technical awareness • User feedback 33 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Finding performance problems § Start with code that works § Don’t assume you know what the problem is § Change one thing at a time § You will make things worse (probably) • Take those changes out § The goal posts are always moving • Stop when it’s good enough 34 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Tools for measuring performance § PROFILER system handle • Line-by-line execution timings • Tool available on PSDN § etime § Logging infrastructure • Useful in production environments • Log. Read utility on PSDN § Wireshark ( http: //www. wireshark. org/ ) • Network analyzer 35 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

R-code & PROPATH § Always use r-code in production • Use –q (Quick Request) parameter § Reduce r-code size • Remove function prototypes • Limit use of GLOBAL variables • Compile with MIN-SIZE option § Keep PROPATH as short as possible • Order entries by frequency of use § Use procedure libraries • Memory-mapped when on same machine 37 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

In Summary § Good performance needs upfront work • Design • Coding § Measure

For More Information, go to… § PSDN • Profiler http: //www. psdn. com/library/entry. jspa? external. ID=280&category. ID=1801 • Log. Read 1. 0 Tool Overview (English & Spanish) http: //www. psdn. com/library/entry. jspa? category. ID=62&external. ID=1841 • Log Read Utility http: //www. psdn. com/library/entry. jspa? category. ID=41&external. ID=349 § 39 Documentation: • Open. Edge® Deployment: Managing ABL Applications DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

Relevant Exchange Sessions § DEV-15: App. Server™ Mode Case Studies § OPS-23: Open. Edge Performance Basics 40 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation

From a developer’s viewpoint, something to consider Optimization matters only when it matters. When it matters, it matters a lot, but until you know that it matters, don't waste a lot of time doing it. Even if you know it matters, you need to know where it matters. Without performance data, you won't know what to optimize, and you'll probably optimize the wrong thing. Joseph M. Newcomer Optimization: Your Worst Enemy http: //www. codeproject. com/KB/tips/optimizationenemy. aspx 41 DEV-31: Designing your ABL Application for Performance © 2008 Progress Software Corporation