Better Performance: ecryptfs or luks via loopback

Hi all,
I'm looking to encrypt a partition on my very old (circa 2000) desktop box cum server. It has an old pata disk drive that holds the / partition (ext4). The partition, however, is really big for a / partition, so I was hoping to reclaim some of that space for an encrypted home directory. My two possible methods to do so:
1) Make a pre-sized file on the / filesystem that I then access via loop-back and encrypt with Luks as detailed here: https://wiki.archlinux.org/index.php/Dm … oop_device
-Which filesystem would work best on top of this whole stack,e.g. btrfs (with lzo compression?), ext4, or something else
2) Use ecryptfs on top of the / ext4 filesystem, as detailed here: https://wiki.archlinux.org/index.php/ECryptfs
My main question: which of these two options would probably have the best performance? I know Luks tends to be, on the whole, faster (at least when encrypting a block device instead of a loop-back device), but does this advantage disappear when stacked via a loop-back device?

Hello! The SATA card should outperform the ide drives but it all depends on what you're doing such as large or small file transfers. For some real improvement hook a 10,000 rpm Raptor drive to the SATA card and put the OS and apps on it. Tom

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Which approach is having better performance in terms of time

For large no of data from more then two diffrent tables which are having relations ,
In Oracle in following two approaches which is having better performance in terms of time( i.e which is having less time) ?
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2. Bunch of simple queries

Because their is a relationship between each of the tables in the simple queries then if you adopt this approach you will have to JOIN in some way, probably via a FOR LOOP in PL/SQL.
In my experience, a single complex SQL statement is the best way to go, join in the database and return the set of data required.
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Difference between Temp table and Variable table and which one is better performance wise?

Hello,
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Check following link to see differences b/w TempTable & TableVariable: http://sqlwithmanoj.com/2010/05/15/temporary-tables-vs-table-variables/
TempTables & TableVariables both use memory & tempDB in similar manner, check this blog post: http://sqlwithmanoj.com/2010/07/20/table-variables-are-not-stored-in-memory-but-in-tempdb/
Performance wise if you are dealing with millions of records then TempTable is ideal, as you can create explicit indexes on top of them. But if there are less records then TableVariables are good suited.
On Tables Variable explicit index are not allowed, if you define a PK column, then a Clustered Index will be created automatically.
But it also depends upon specific scenarios you are dealing with , can you share it?
~manoj | email: http://scr.im/m22g
http://sqlwithmanoj.wordpress.com
MCCA 2011 | My FB Page

How to setup airport time capsule to get better performance?

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What wifi channel need choose to?

What is the best way to do that?
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I need a clarification : Can I use EJBs instead of helper classes for better performance and less network traffic?

My application was designed based on MVC Architecture. But I made some changes to HMV base on my requirements. Servlet invoke helper classes, helper class uses EJBs to communicate with the database. Jsps also uses EJBs to backtrack the results.
I have two EJBs(Stateless), one Servlet, nearly 70 helperclasses, and nearly 800 jsps. Servlet acts as Controler and all database transactions done through EJBs only. Helper classes are having business logic. Based on the request relevant helper classed is invoked by the Servlet, and all database transactions are done through EJBs. Session scope is 'Page' only.
Now I am planning to use EJBs(for business logic) instead on Helper Classes. But before going to do that I need some clarification regarding Network traffic and for better usage of Container resources.
Please suggest me which method (is Helper classes or Using EJBs) is perferable
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2) for less network traffic
3) for better container resource utilization
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Please give detailed explanation.
thank you,
sudheer

Please suggest me which method (is Helper classes or Using EJBs) is perferable :
1) to get better performance
EJB's have quite a lot of overhead associated with them to support transactions and remoteability. A non-EJB helper class will almost always outperform an EJB. Often considerably. If you plan on making your 70 helper classes EJB's you should expect to see a dramatic decrease in maximum throughput.
2) for less network traffic
There should be no difference. Both architectures will probably make the exact same JDBC calls from the RDBMS's perspective. And since the EJB's and JSP's are co-located there won't be any other additional overhead there either. (You are co-locating your JSP's and EJB's, aren't you?)
3) for better container resource utilization
Again, the EJB version will consume a lot more container resources.

Any general tips on getting better performance out of multi table insert?

I have been struggling with coding a multi table insert which is the first time I ever use one and my Oracle skills are pretty poor in general so now that the query is built and works fine I am sad to see its quite slow.
I have checked numerous articles on optimizing but the things I try dont seem to get me much better performance.
First let me describe my scenario to see if you agree that my performance is slow...
its an insert all command, which ends up inserting into 5 separate tables, conditionally (at least 4 inserts, sometimes 5 but the fifth is the smallest table). Some stats on these tables as follows:
Source table: 5.3M rows, ~150 columns wide. Parallel degree 4. everything else default.
Target table 1: 0 rows, 27 columns wide. Parallel 4. everything else default.
Target table 2: 0 rows, 63 columns wide. Parallel 4. default.
Target table 3: 0 rows, 33 columns wide. Parallel 4. default.
Target table 4: 0 rows, 9 columns wide. Parallel 4. default.
Target table 5: 0 rows, 13 columns wide. Parallel 4. default.
The parallelism is just about the only customization I myself have done. Why 4? I dont know it's pretty arbitrary to be honest.
Indexes?
Table 1 has 3 index + PK.
Table 2 has 0 index + FK + PK.
Table 3 has 4 index + FK + PK
Table 4 has 3 index + FK + PK
Table 5 has 4 index + FK + PK
None of the indexes are anything crazy, maybe 3 or 4 of all of them are on multiple columns, 2-3 max. The rest are on single columns.
The query itself looks something like this:
insert /*+ append */ all
when 1=1 then
into table1 (...) values (...)
into table2 (...) values (...)
when a=b then
into table3 (...) values (...)
when a=c then
into table3 (...) values (...)
when p=q then
into table4(...) values (...)
when x=y then
into table5(...) values (...)
select .... from source_table
Hints I tried are with append, without append, and parallel (though adding parallel seemed to make the query behave in serial, according to my session browser).
Now for the performance:
It does about 8,000 rows per minute on table1. So that means it should also have that much in table2, table3 and table4, and then a subset of that in table5.
Does that seem normal or am I expecting too much?
I find articles talking about millions of rows per minute... Obviously i dont think I can achieve that much... but maybe 30k or so on each table is a reasonable goal?
If it seems my performance is slow, what else do you think I should try? Is there any information I may try to get to see if maybe its a poorly configured database for this?
P.S. Is it possible I can run this so that it commits every x rows or something? I had the heartbreaking event of a network issue giving me this sudden "ora-25402: transaction must roll back" after it was running for 3.5 hours. So I lost all the progress it made... have to start over. plus i wonder if the sheer amount of data being queued for commit/rollback is causing some of the problem?
Edited by: trant on Jun 27, 2011 9:29 PM

Looks like there are about 54 sessions on my database, 7 of the sessions belong to me (2 taken by TOAD and 4 by my parallel slave sessions and 1 by the master of those 4)
In v$session_event there are 546 rows, if i filter it to the SIDs of my current session and order my micro_wait_time desc:
510     events in waitclass Other     30670     9161     329759     10.75     196     3297590639     1736664284     1893977003     0     Other
512     events in waitclass Other     32428     10920     329728     10.17     196     3297276553     1736664284     1893977003     0     Other
243     events in waitclass Other     21513     5     329594     15.32     196     3295935977     1736664284     1893977003     0     Other
223     events in waitclass Other     21570     52     329590     15.28     196     3295898897     1736664284     1893977003     0     Other
241     row cache lock     1273669     0     42137     0.03     267     421374408     1714089451     3875070507     4     Concurrency
241     events in waitclass Other     614793     0     34266     0.06     12     342660764     1736664284     1893977003     0     Other
241     db file sequential read     13323     0     3948     0.3     13     39475015     2652584166     1740759767     8     User I/O
241     SQL*Net message from client     7     0     1608     229.65     1566     16075283     1421975091     2723168908     6     Idle
241     log file switch completion     83     0     459     5.54     73     4594763     3834950329     3290255840     2     Configuration
241     gc current grant 2-way     5023     0     159     0.03     0     1591377     2685450749     3871361733     11     Cluster
241     os thread startup     4     0     55     13.82     26     552895     86156091     3875070507     4     Concurrency
241     enq: HW - contention     574     0     38     0.07     0     378395     1645217925     3290255840     2     Configuration
512     PX Deq: Execution Msg     3     0     28     9.45     28     283374     98582416     2723168908     6     Idle
243     PX Deq: Execution Msg     3     0     27     9.1     27     272983     98582416     2723168908     6     Idle
223     PX Deq: Execution Msg     3     0     25     8.26     24     247673     98582416     2723168908     6     Idle
510     PX Deq: Execution Msg     3     0     24     7.86     23     235777     98582416     2723168908     6     Idle
243     PX Deq Credit: need buffer     1     0     17     17.2     17     171964     2267953574     2723168908     6     Idle
223     PX Deq Credit: need buffer     1     0     16     15.92     16     159230     2267953574     2723168908     6     Idle
512     PX Deq Credit: need buffer     1     0     16     15.84     16     158420     2267953574     2723168908     6     Idle
510     direct path read     360     0     15     0.04     4     153411     3926164927     1740759767     8     User I/O
243     direct path read     352     0     13     0.04     6     134188     3926164927     1740759767     8     User I/O
223     direct path read     359     0     13     0.04     5     129859     3926164927     1740759767     8     User I/O
241     PX Deq: Execute Reply     6     0     13     2.12     10     127246     2599037852     2723168908     6     Idle
510     PX Deq Credit: need buffer     1     0     12     12.28     12     122777     2267953574     2723168908     6     Idle
512     direct path read     351     0     12     0.03     5     121579     3926164927     1740759767     8     User I/O
241     PX Deq: Parse Reply     7     0     9     1.28     6     89348     4255662421     2723168908     6     Idle
241     SQL*Net break/reset to client     2     0     6     2.91     6     58253     1963888671     4217450380     1     Application
241     log file sync     1     0     5     5.14     5     51417     1328744198     3386400367     5     Commit
510     cursor: pin S wait on X     3     2     2     0.83     1     24922     1729366244     3875070507     4     Concurrency
512     cursor: pin S wait on X     2     2     2     1.07     1     21407     1729366244     3875070507     4     Concurrency
243     cursor: pin S wait on X     2     2     2     1.06     1     21251     1729366244     3875070507     4     Concurrency
241     library cache lock     29     0     1     0.05     0     13228     916468430     3875070507     4     Concurrency
241     PX Deq: Join ACK     4     0     0     0.07     0     2789     4205438796     2723168908     6     Idle
241     SQL*Net more data from client     6     0     0     0.04     0     2474     3530226808     2000153315     7     Network
241     gc current block 2-way     5     0     0     0.04     0     2090     111015833     3871361733     11     Cluster
241     enq: KO - fast object checkpoint     4     0     0     0.04     0     1735     4205197519     4217450380     1     Application
241     gc current grant busy     4     0     0     0.03     0     1337     2277737081     3871361733     11     Cluster
241     gc cr block 2-way     1     0     0     0.06     0     586     737661873     3871361733     11     Cluster
223     db file sequential read     1     0     0     0.05     0     461     2652584166     1740759767     8     User I/O
223     gc current block 2-way     1     0     0     0.05     0     452     111015833     3871361733     11     Cluster
241     latch: row cache objects     2     0     0     0.02     0     434     1117386924     3875070507     4     Concurrency
241     enq: TM - contention     1     0     0     0.04     0     379     668627480     4217450380     1     Application
512     PX Deq: Msg Fragment     4     0     0     0.01     0     269     77145095     2723168908     6     Idle
241     latch: library cache     3     0     0     0.01     0     243     589947255     3875070507     4     Concurrency
510     PX Deq: Msg Fragment     3     0     0     0.01     0     215     77145095     2723168908     6     Idle
223     PX Deq: Msg Fragment     4     0     0     0     0     145     77145095     2723168908     6     Idle
241     buffer busy waits     1     0     0     0.01     0     142     2161531084     3875070507     4     Concurrency
243     PX Deq: Msg Fragment     2     0     0     0     0     84     77145095     2723168908     6     Idle
241     latch: cache buffers chains     4     0     0     0     0     73     2779959231     3875070507     4     Concurrency
241     SQL*Net message to client     7     0     0     0     0     51     2067390145     2000153315     7     Network
(yikes, is there a way to wrap that in equivalent of other forums' tag?)
v$session_wait;
223     835     PX Deq Credit: send blkd     sleeptime/senderid     268697599     000000001003FFFF     passes     1     0000000000000001     qref     0     00     1893977003     0     Other     0     10     WAITING
241     22819     row cache lock     cache id     13     000000000000000D     mode     0     00     request     5     0000000000000005     3875070507     4     Concurrency     -1     0     WAITED SHORT TIME
243     747     PX Deq Credit: send blkd     sleeptime/senderid     268697599     000000001003FFFF     passes     1     0000000000000001     qref     0     00     1893977003     0     Other     0     7     WAITING
510     10729     PX Deq Credit: send blkd     sleeptime/senderid     268697599     000000001003FFFF     passes     1     0000000000000001     qref     0     00     1893977003     0     Other     0     2     WAITING
512     12718     PX Deq Credit: send blkd     sleeptime/senderid     268697599     000000001003FFFF     passes     1     0000000000000001     qref     0     00     1893977003     0     Other     0     4     WAITING
v$sess_io:
223     0     5779     5741     0     0
241     38773810     2544298     15107     27274891     0
243     0     5702     5688     0     0
510     0     5729     5724     0     0
512     0     5682     5678     0     0

I need better performance from my computer. Could someone point me in the right direction?

I do a lot of video editing for work. I am currently using the Creative Cloud, and the programs I use most frequently are Premiere Pro CS6, Photoshop CS6, and Encore. My issue is that when I am rendering video in Premiere Pro, and most importantly, transcoding in Encore for BluRay discs, I am getting severe lag from my computer. It basically uses the majority of my computer's resources and doesn't allow me to do much else. This means, that I can't do other work while stuff is rendering or transcoding. I had this computer built specifically for video editing and need to know which direction to go in for an upgrade to get some better performance, and allow me to do other work.
For the record, I do have MPE: GPU Acceleration turned ON, and I have 12GBs of RAM alloted for Adobe in Premiere Pro's settings, and 4GBs left for "other".
Here is my computer:
- Dell Precision T7600
- Windows 7 Professional, 64-bit
- DUAL Intel Xeon CPU E-2620 - 2.0GHz 6-core Processors
- 16GBs of RAM
- 256GB SSD as my primary drive. This is where the majority of my work is performed.
- Three 2TB secondary drives in a RAID5 configuration. This is solely for backing up data after I have worked on it. I don't really use this to work off of.
- nVidia Quadro 4000 2GB video card
When I am rendering or transcoding, my processor(s) performance fluctuates between 50%-70%, with all 12 cores active and being used. My physical memory is basically ALL used up while this is happening.
Here is where I am at on the issue. I put in a request for more RAM (32GBs), this way I can allot around 25GBs of RAM to the Adobe suite, leaving more than enough to do other things. I was told that this was not the right direction to go in. I was told that since my CPUs are working around 50-70%, it means that my video card isn't pulling enough weight. I was told that the first step in upgrading this machine that we should take, is to replace my 2GB video card with a 4GB video card, and that will fix these performance issues that I am having, not RAM.
This is the first machine that has been built over here for this purpose, so it is a learning process for us. I was hoping someone here could give a little insight to my situation.
Thanks for any help.

You have a couple of issues with this system:
Slow E5-2620's. You would be much better off with E5-2687W's
Limited memory. 32 GB is around bare minimum for a dual processor system.
Outdated Quadro 4000 card, which is very slow in comparison to newer cards and is generally not used when transcoding.
Far insufficient disk setup. You need way more disks.
A software raid5 carries a lot of overhead.
The crippled BIOS of Dell does not allow overclocking.
The SSD may suffer from severe 'stable state' performance degradation, reducing performance even more.
You would not be the first to leave a Dell in the configuration it came in. If that is the case, you need a lot of tuning to get it to run decently.
Second thing to consider is what source material are you transcoding to what destination format? If you start with AVCHD material and your destination is MPEG2-DVD, the internal workings of PR may look like this:
Convert AVCHD material to an internal intermediate, which is solely CPU bound. No GPU involvement.
Rescale the internal intermediate to DVD dimensions, which is MPE accelerated, so heavy GPU involvement.
Adjust the frame rate from 29.97 to 23.976, which again is MPE accelerated, so GPU bound.
Recode the rescaled and frame-blended internal intermediate to MPEG2-DVD codec, which is again solely CPU bound.
Apply effects to the MPEG2-DVD encoded material, which can be CPU bound for non-accelerated effects and GPU bound for accelerated effects.
Write the end result to disk, which is disk performance related.
If you export AVCHD to H.264-BR the GPU is out of the game altogether, since all transcoding is purely CPU based, assuming there is no frame blending going on. Then all the limitations of the Dell show up, as you noticed.

In PI 7.1 better performance is reached using RFC or Proxy?

Hello Experts,
As with PI 7.1 which one would be better option to have better performance?
1)Proxy which goes through the Integration Engine by omiting Advance adaptor Engine
2)RFC which goes through the AAE by omiting Integration Engine
As we know there are alot of advantages of Proxies over RFC:
1. Proxy communication always by passes the Adapter Engine and will directly interact with the application system and Integration engine. So it will give us better performance.
2. Proxies communicate with the XI server by means of native SOAP calls over HTTP.
3. Easy to handle messages with ABAP programming if it is ABAP Proxy .
4. Proxy is good for large volumes of data. we can catch and persist the errors ( both system & application fault ) which was generated by Proxy setting.
Thanks in Advance
Rajeev

Hey
More than the performance,its a question of requirement.
There are several restrictions which you need to consider before using AAE.To name a few
IDOC,HHTP adapter wont be available
No support for ABAP mapping
No support for BPM
No support for proxy
No support for Multimapping,content based routing ( in first release)
So if you want to use any of the above you cant use AAE in first place.but performance is significantly improved,upto 4 times better that simple AE-IE
/people/william.li/blog/2008/01/10/advanced-adapter-engine-configuration-in-pi-71
check the above blog and the article mentioned in it.
Now coming to proxy,it supports all the above and performance is not that bad either.
so it all boils down to what your requirements are:)
Thanks
Aamir

How to get better perform here

hi there,
bellow code is using with in the loop. how can i modify to get better performance.
SELECT knumv kposn kwert FROM konv
                                INTO CORRESPONDING FIELDS OF lt_konv
                                 WHERE knumv EQ lt_output-knumv
                                 AND kposn EQ lt_output-posnr
                                 AND kschl EQ 'VPRS'.
        COLLECT lt_konv.
      ENDSELECT.
thx in adv.

the better solution for the select statement whould be to use the aggreagte function sum for the field kwert:
SELECT knumv kposn sum(kwert)
             FROM konv
             INTO CORRESPONDING FIELDS OF table lt_konv
             WHERE knumv EQ lt_output-knumv
                   AND kposn EQ lt_output-posnr
                   AND kschl EQ 'VPRS'.
The select is inside the loop an lt_output.
Aggregate functions and FOR ALL ENTRIES can not be combined, the
FOR ALL ENTRIES is a select distinct !!!
So you must leave the loop around the select and you can't use the FOR ALL ENTRIES, but this is o.k.,
Siegfried

Which gives better performance in webi using display attr or nav attr -

Hello all,
We are using the Bex query as the datasource for our universes and the end user is using the Web Intelligence as the reporting tool (rich client and infoview) we have employee as one of the infoobject in the cube.
Now employee has a lot of attributes which the user wants to use for reporting (delivered employee infoobject has quite a few attr), we are making some of them as Nav attr like Org unit since they are time dependent and the end user will need to put in the key date to bring the employees from right org unit.
We have enhanced the employee attr to have the all address information of the employee (Z fileds) and we have made those nav attr in RSd1.
So my question is should we make the address Z fields as nav attr in cube as well and use those objects in webi or can we use the objects in webi which fall under employee like details (green icons) rather than separate object.
Please let me know what will keep better performance and what is the best practice.
Thanks you in advance and appreciate everyone's help
Edited by: Cathy on Jun 16, 2011 7:35 AM

Hi,
BEx Query Design Recommendations:
"Reduce Usage of Navigational Attributes as much as possible Also, if simply displaying a Characteristicu2019s Attribute, DO NOT use the Navigational Attribute u2013 rather utilize the Characteristic Attribute for display in the report This avoids unneeded JOINS, and also reduces total number of rows transferred to WebI"
Source : SAP Document
Thanks,
Amit

Scale out SSAS server for better performance

HI
i have a sharepoint farm
running performance point service in a server where ANaylysis srver,reporting server installed
and we have anyalysis server dbs and cubes
and a wfe server where secure store service running
we have
1) application server + domain controller
2) two wfes
1) sql server sharepoint
1) SSAS server ( analysis server dbs+ reporting server)
here how i scaled out my SSAS server for better performance
adil

Just trying to get a definitive answer to the question of can we use a Shared VHDX in a SOFS Cluster which will be used to store VHDX files?
We have a 2012 R2 RDS Solution and store the User Profile Disks (UPD) on a SOFS Cluster that uses "traditional" storage from a SAN. We are planning on creating a new SOFS Cluster and wondered if we can use a shared VHDX instead of CSV as the storage that
will then be used to store the UPDs (one VHDX file per user).
Cheers for now
Russell
Sure you can do it. See:
Deploy a Guest Cluster Using a Shared Virtual Hard Disk
http://technet.microsoft.com/en-us/library/dn265980.aspx
Scenario 2: Hyper-V failover cluster using file-based storage in a separate Scale-Out File Server
This scenario uses Server Message Block (SMB) file-based storage as the location of the shared .vhdx files. You must deploy a Scale-Out File Server and create an SMB file share as the storage location. You also need a separate Hyper-V failover cluster.
The following table describes the physical host prerequisites.
Cluster Type
Requirements
Scale-Out File Server
At least two servers that are running Windows Server 2012 R2.
The servers must be members of the same Active Directory domain.
The servers must meet the requirements for failover clustering.
For more information, see Failover Clustering Hardware Requirements and Storage Options and Validate
Hardware for a Failover Cluster.
The servers must have access to block-level storage, which you can add as shared storage to the physical cluster. This storage can be iSCSI, Fibre Channel, SAS, or clustered storage spaces that use a set of shared SAS JBOD enclosures.
StarWind VSAN [Virtual SAN] clusters Hyper-V without SAS, Fibre Channel, SMB 3.0 or iSCSI, uses Ethernet to mirror internally mounted SATA disks between hosts.

Will insert (ignore duplicates) have a better performance than merge?

Will insert (ignore duplicates) have a better performance than merge (insert if not duplicate)?

Ok. Here is exactly what is happenning -
We had a table with no unique index on it. We used 'insert all' statement to insert record.
But later when we found duplicates in there we started removing them manually.
Now, to resolve the issue we added unique index and added exception handling to ignore DUP_VAL_ON_INDEX exception.
But with this all records being inserted by 'INSERT ALL' statement gets ignored even if only one record is duplicate.
Hence we have finally replaced 'insert all' with merge statement. Which inserts only if a corresponding record is not found (match based on column in unique index) in the table.
But I am wondering how much performance will get impacted.

Which method has a better performance ?

Hello !
I'm using entity framework , and I have several cases where I should run a query than return some parent items , and after I display these parents and the related children in one report.
I want to know which of these methods have the better performance : ( or is there any other better method ??? )
Method1: (the childs collection are loaded later , using lazy loading)
Dim lista as IQueryable(Of MyObj) = (From t In context.MyObjs Where(..condition..) select t).Tolist
Method2:
Dim lista as IQueryable(Of MyObj) = (From t In context.MyObjs Where(..condition..) _
.Include(Function(t2) t2.Childs1) _
.Include(Function(t2) t2.Childs2) _
.Include(Function(t2) t2.Childs2.Child22) _
.Include(Function(t2) t2.Childs1.Childs11) _
.Include(Function(t2) t2.Childs1.Childs12) _
Select t).ToList
Method3:
Dim lista as IQueryable(Of MyObj)
Dim lst= (From t2 In context.MyObjs Where(..condition..) Select New with _
{ .Parent=t2
.ch1=t2.Childs1 _
.ch2=t2.Childs2 _
.ch21=t2.Childs2.Child21) _
.ch11=t2.Childs1.Childs11) _
.ch12= t2.Childs1.Childs12 _
).ToList
lista=lst.Select(Function(t2) t2.parent)
I noticed that the first method cause the report to open very slow. Also I read somewhere that Include() cause repeat of parent items?
But anyway I want a professional opinion in general for the three methods.
Thank you !

Hello,
As far as I know, the Entity Framework offers two ways to load related data after the fact. The first is called lazy loading and, with the appropriate settings, it happens automatically. In your case, your first method uses the last loading, while the second
and third are the same actually, both of them are Eager Loading. (In VB, if you could check use code as “DbContext.Database.Log = Sub(val) Diagnostics.Trace.WriteLine(val)” to see the actually generated sql statement, you could see the third and second query
would generate a join syntax). Since you mentions, the lazy loading way is low performance, you could use either the second or third one.
>>Also I read somewhere that Include() cause repeat of parent items?
For this, nor sure if you worry it would firstly use lazy loading and then use eager loading, however, in my test, I do not see this behavior, the Entity Framework seems to be smart enough to use one mode to load data at the same time. Or you could disable
its lazy loading when using eager loading:
context.ContextOptions.LazyLoadingEnabled = false
Regards.
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Better performance setting...

Hi everyone!
I keep my PowerBook on pretty much all the time because I need it for emails. It's now 3 years old and although it runs well it seems a bit faster with the Better Performance setting than the Normal. Is there any harm in leaving it with this setting all the time?
Thanks,
Reg

Thanks for the reply!
Ok that makes me feel better...yes sometimes if I need better battery life I will lower it to Normal when unplugged...but most of the time I use it plugged anyways...
Now I can feel good to always use Better Performance...I don't know if others can notice the difference but I can with all the latest upgrades in software...
Thanks again,
Reg

Better Performance: ecryptfs or luks via loopback

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