Introduction

One of the great availability and scaling features of Caché is Enterprise Cache Protocol (ECP). With consideration during application development distributed processing using ECP allows a scale out architecture for Caché applications. Application processing can scale to very high rates from a single application server to the processing power of up to 255 application servers with no application changes.

Checking if Directory or File Exists:

Outlined below is an example of how to check if a directory exists:

Set directoryName="c:\temp\nosuchdir"

/* Check for existence of a directory - Return Value:  0 - directory does not exist;  1 - directory does exist  */

Set directoryExists=##class(%File).DirectoryExists(directoryName)

If ('directoryExists)  // do the processing for when a directory does not exist

Outlined below is an example of how to check if a file exists:

Problem:

Caché prints to printers in a manner somewhat different from other Windows applications. Caché sends the data directly to the GDI Printer, without the usual interface. This is because the GUI interface can only be shown on a system desktop session and not in web browser and terminal sessions. Some printer drivers have problems with this method of printing.

Is this the problem you are having?

Myself and the other Technology Architects often have to explain to customers and vendors Caché IO requirements and the way that Caché applications will use storage systems. The following tables are useful when explaining typical Caché IO profile and requirements for a transactional database application with customers and vendors. The original tables were created by Mark Bolinsky.

In future posts I will be discussing more about storage IO so am also posting these tables now as a reference for those articles.

The release of IBM POWER 8 processors with AIX 7.1 introduced up to 8 SMT threads per processor core (logical or physical). Which SMT level (1, 2, 4, or 8) to use can be confusing and varies based on multiple factors. This article is meant to help with a starting point for your specific application.

Firstly, if running on a version of 2014.x or older, it is advised to use SMT 4 or lower. SMT 8 with those older versions of Cache' has shown a decline in performance and scaling in benchmarking applications.

Introduction

The field test of Caché 2016.2 has been available for quite some time and I would like to focus on one of the substantial features that is new in this version: the document data model. This model is a natural addition to the multiple ways we support for handling data including Objects, Tables and Multidimensional arrays. It makes the platform more flexible and suitable for even more use cases.

Cache tricks

Several years ago, long before Developer Community Portal was launched, I published a series of Caché tricks at one of Czech web sites. In this article, I’m posting translated version of one of them.

Capturing output of someone else’s methods or routines

Suppose you, or someone else created a useful method or routine, that was producing some computation that you’d like to benefit from, but the routine was writing output to process principal device.

You would like to use the data, but you need it not written to a device, but assigned to a variable. And, for any reason, you can’t modify the code. What can you do?

During recent large scale benchmarking activities, we were seeing excessive %sys CPU time that negatively impacted scaling of the application.

Problem

In OS X 10.8 and earlier, PHP was built with ODBC support, making it easy to connect to a Caché database:

$ php -r 'phpinfo();' |grep 'ODBC Support'
ODBC Support => enabled

However, this support was removed in OS X 10.9:

Have some free text fields in your application that you wish you could search efficiently? Tried using some methods before but found out that they just cannot match the performance needs of your customers? Do I have one weird trick that will solve all your problems? Don’t you already know!? All I do is bring great solutions to your performance pitfalls!

As usual, if you want the TL;DR (too long; didn’t read) version, skip to the end. Just know you are hurting my feelings.

InterSystems is happy to announce the availability of our newest Data Platforms release: Caché and Ensemble 2016.2

The highlights of 2016.2 are:

Ansible helped me solve the problem of quickly deploying Caché and application components for Data Platforms benchmarks. You can use the same tools and methodology for standing up your test labs, training systems, development or other environments. If you deploy applications at customer sites you could automate much of the deployment and ensure that system, Caché and your application are configured to your applications best practice standards.

Does anyone have any experience with getting, unfortunately, an older version of Cache to authenticate via SMTP to send email? I have verified that the settings are set up properly on the mailbox as I have successfully sent an email from a LAMP server, which comes from the same IP address.

If you have any thoughts, I would greatly appreciate it.

This is the error I receive

ERROR #6034: SMTP server connection failed during MAIL FROM command: <READ>zSend+105^%Net.SMTP.1.