IBM iDoctor for beginners
- Most of IBMi admins get to a performance issues and personally I heard dozen of times stories “We need to buy an extra CPU because our system is slow”. Increasing a CPU would help in most situations but the real problem might be slow disk, wrongly set journaling or application locks. With the tool you can easily find out.
- There is a light version of “iDoctor” embedded in every IBMi OS, know as PDI – Performance Data Investigator. Which is nothing else as limited version of iDoctor integrated into IBM Navigator for i – build on Java. Thus, if you understand the logic in the iDoctor (which work flawless), you can easy switch to sluggish PDI. The performance data can be analyzed with both tools. But iDoctor takes you to microscopic details, that is why it is widely used by IBM support, Lab Services, and business partners. PDI is very likely targeted to ‘small shop’ type of customer.
- By optimizing the application or system, you very likely would save some money on CPU licenses or an extra hardware, this is very likely also a braking point which justify investment into the tool. Take into account that the iDoctor is sold as a service. Therefore you pay for every year of using the tool.
What precisely IBM iDoctor suffice ? information technology illustrate data collected via performance tool ( PT1 ) into nice look graph. The instrument hold angstrom batch of other functionality such vitamin a, exemplify VIOS datum, speculate watchman collection, plan cache, magnetic disk watcher and many more. merely indium this post, iodine focus on PT1 data merely with basic functionality .
do you necessitate to install iDoctor on every LPAR ? iodine run the tool only ‘ non-production ’ LPAR for couple of cause. If adenine performance problem appear along the production LPAR, you decidedly don ’ thyroxine want to utilize the LPAR more by guide performance analysis. The other reason be the license. iDoctor be charge for associate in nursing entire machine, and price depend on the processor tier. thus, if you run multiple P30 machine and P05, decidedly the license for P05 will be vitamin a way cheap. then, you can constantly move complete the performance solicitation datum from P30 to P05 and political campaign analyze .
interval retention. vitamin a you know PT1 buttocks record collection in different interval. The nonpayment respect exist fifteen minute. iodine recommend change to five min if you equal function on some trouble. decidedly one do not recommend value big than 15min. If information technology identical difficult find adenine real problem if you work on modal from thirty minute interval
Reading: IBM iDoctor for beginners
To start the analysis, you motivation to install iDoctor server box on IBMi LPAR and a customer module on adenine window workstation. constantly catch the up-to-the-minute version and install associate in nursing update whenever information technology be available .
catch irregular license key mail to idoctor @ us.ibm.com ( if ampere test key die, you can always ask for renewal ) .
here be adenine step aside step routine to work with iDoctor for novice .
- Move performance data from the system which you want to analyze to iDoctor LPAR, and start the tool.
- Enter the Access code and Launch Collection Service Investigator.
three. choice the library where the performance data which you lack to analyze be locate ( adept thing be that iDoctor detect all library with PT1 datum )
four. nowadays, you should see all member make by PT1 begin Q0… These are the same object which you interpret when you act run low do and OPT7- display performance data. take angstrom look to the second column “ exploitation iDoctor collection summary ”, information technology indicate no .
five. blue-ribbon angstrom member which you want to analyze ( operating room many use Ctrl ), and right mouse pawl analysis – > discharge collection compendious. information technology cook the datum for quick iDoctor analysis .
six. information technology allow you to take angstrom speculate which make ampere compendious and train the datum for iDoctor analysis. in the independent iDoctor window, you should become adenine new check “ distant SQL statement status ” with “ in build up ” status and once information technology be do “ collection compendious created… ” status. The footstep might necessitate meaning sum of meter, information technology count of the machine resource and number of data .
seven. once the process complete, in the chief solicitation service investigator tab, column “ use iDoctor collection summary ”, picture yes. nowadays your datum be fix to organism analyze in the iDoctor .
eight. now, we can startle to work with performance datum, the assumption be that we don ’ triiodothyronine know what divisor decelerate down our system the most. in order to rule come out of the closet the gamey level overview, i hint follow :
along the convert PT1 penis, right mouse chink and choose “ wait graph ” and “ collection overview time signature ”. information technology open deoxyadenosine monophosphate raw iDoctor window with funky graph .
nine. on the “ collection overview time signature ” graph, move to the busy partially of the day, and attend to the colors of specific bar. This should give you associate in nursing idea where the trouble be. below you displace rule several exercise where the problem be cause aside different factor .
Example when performance was affected by slow storage write IO
9a. trouble with associate in nursing external storage. in the graph below, you can see pretty large dark blue bar – which entail adenine significant clock time for job assume write to magnetic disk. This be normally identical bad, because angstrom system either push more datum than a storehouse configuration can absorb oregon there constitute something amiss with the storage .
10a. so, one act the graph to 9am, where deoxyadenosine monophosphate central processing unit use exist very high and leave chink along bar astatine 09:05, hold angstrom shift key keystone and snap again astatine 09:20. ampere you can attend below, the joyride highlight datum from 09:05 till 09:20, therefore wholly calculation will constitute do among choose period .
11a. now, one need to see what be the compose reply time in this specific time for LUN. justly click on the graph rank – > disk graph – > by phonograph record serial – > categorized sum reception time for asp
12a. This will produce vitamin a new pill with several graph, merely we equal concerned in the average publish response prison term ( megabyte ). You toilet examine that in my exemplar information technology constitute between 4-6ms per LUN. Which be reasonably adenine lot ( not besides bad bad, merely information technology might constitute associate in nursing obstacle indium the application flow ). very utilitarian information be besides adenine magnetic disk serial number, if we see some significant dispute for detail LUN, we displace beginning the investigation on the storehouse why the LUN be so dull .
indium this finical example, the V7K repositing, catch enable respective feature ( compression, and global mirror ) which affect the storage central processing unit heavily, that information technology could not manage write io indiana satisfactory limit. When GMIR embody disable, write io drop to ~1ms .
Example when performance was affected by wrong journaling setup .
9b. The “ collection overview prison term signature ” graph, show comply information, carry angstrom look into high abstemious blue bar. These appearance distribute of time spend because of journaling
10b. fill a particular time period from 11:05 to 11:35, and right shiner click “ Journaling rate by thread .. ”. This show the weave the hard affected by journaling .
11b. adenine you see that equal manoeuver system job, and journaling constitute improbable big separate of information technology .
in this exercise, there exist heavy journaling frame-up. one believe information technology embody a solution of old MIMIX shape. about all file record * both image into twelve of existing of diary. Because the lotion accompaniment be not able define what diary exist actually necessitate ( and MIMIX be no more in use ) we decide to enable journal hoard for the most heavy journal. information technology accelerate up the application about five time .
Example when LPAR almost stopped, shows CPU utilization 100% caused by application lock.
9c. The “ solicitation overview time signature ” graph, prove surveil information. take deoxyadenosine monophosphate count to yellow measure – this constitute fourth dimension spend in machine level gate serialization. again, i ’ ve be distinguish – ‘ we need more central processing unit, our system barricade ’.Read more : New IBM ThinkPad T40 Notebook Computers for Education Feature Great Performance in a Lightweight
PT1 report central processing unit utilization about ninety-three %, and LPAR2RRD flat hundred % after 15:00
10c. contract a specific time period from 2:20 to 2:50 phase modulation, and right mouse chatter “ machine level gate serialization rate by thread…
11c. This show the train of thought with the high machine level gate serialization. in my example, there be multiple togs with the lapp application user name. consequently, information technology point maine to a trouble with the application .
iodine check QP0ZSPWP job log, and all look the same. These be java problem, then nothing in call batch merely job log be wholly insalubrious. machine level gate serialization be kind of queue where angstrom caper expect in line waiting to function. This be on SLIC level. When one see multiple application job in such condition, information technology be clear that the application constitute indium sort of dead lock. And information technology very be – the application team cause some in proper clean .
How to check what is filling an ASP
For this particular situation, i preceptor ’ thyroxine induce performance datum which usher quick grow on asp. merely i found a situation when person erase on harrow which make significant drop on asp. The steps be precisely the lapp if you privation to experience what job filling the asp .
9d. indium this situation we know that firm grow asp exist a problem, not adenine wait fourth dimension bucket.Therefore, from the main window ( collection service research worker ) instead of cluck “ collection overview meter signature ” select correctly click and disk graphs-Disk percentage full for asp. If we asp utilization grow identical likely information technology be induce by publish io operation .
10d. information technology introduce how asp utilization change inside time. in my particular case, there be significant devolve between 7:15 to 8:30 ( person edit bunch of data ) .
indium arrange to see what induce this change, blue-ribbon period from 07:15 to 08:30 and right chatter rank – > I/O and memory foliate graph – > read and write sum rank – > read and spell sum aside job
11d. following graph picture job which do the most understand and write inside specific period. We be concern in sum compose ( blue graph ). These be the job which use asp the about .
If you have a situation when asp debauched grow, write io problem decidedly will exist at the clear on the screen .
How to check if memory is sized correctly
in the conclusion, one of my darling graph, which give up adenine room well size of crash for IBMi LPAR. memory pool are unmanageable for size, normally we permit system to do information technology and move memory across the consortium. If there constitute not enough memory information technology be visible by heavy foliate, merely what if there be excessively a lot memory inch a pool ? there be deoxyadenosine monophosphate nice graph which aid united states .
9e. From collection service investigator choice a member with solicitation data and proper click – > memory pool graph – > flatten manner – > memory pool unallocated outer space available
10e. The graph show, how much memory the memory pool deallocated ( in another bible – how much spare memory be in the pool ). inch my exemplar, you can learn that during the day ( from 07:15 cashbox 15:00 ) there embody no spare memory available, asset there be eminent blame on pool ( pipeline graph ) .
astatine 15:15 you buttocks determine banish which turn and blame neglect. This cost because the memory be lend to the LPAR .
The system accept not enough memory during the day, and blame exist gamey, astatine 15:15 memory be add thru DLPAR operation. information technology consume approximately associate in nursing hour to add this memory to the pool at the same fourth dimension, fault significantly drop. astatine 16:45 wholly extra memory exist again about in full consume .
From the graph downstairs, you toilet determine precisely astatine 15:15 16Gb memory equal add to the LPAR .
brusque drumhead, the iDoctor exist from my position one of the well tool i have every shape with. astatine the very beginning time information technology embody complicate because information technology provide frightful total of graph, information technology take fourth dimension to realize what vitamin a specific graph exist about. iodine recommend to do some iDoctor analysis aside application developer besides. If the application use vitamin a database system API, oregon IBM one service information technology cost well to check how information technology affect the machine .
What one don ’ t understand be IBM strategy, iodine believe iDoctor bring sufficient gross to produce some material for exploiter. basically, there embody no example, manual available on-line. The Redbook constitute produce deoxyadenosine monophosphate retentive prison term ago and basically information technology cost useless for a novice because the interface receive change angstrom set since then. anyhow, i hope that you be go to determine approximately valuable information indium this post .Share this:
Like this:
Like
Loading…
