Article
· Nov 9, 2016 5m read
How the Ensemble Scheduler Works

The Ensemble Scheduler is used for automatically turning on and off business hosts at certain dates and times. You could use it if, for example, you wanted to only run a business host from 9am to 5pm every day. Conversely, if you want do to trigger an event to occurr at a specific time, for example, a job running at 1am to batch up and send off all the previous day's transactions in one file, we recommend other methods such as the Task Manager.

8 5
3 3.4K
Article
· Sep 22, 2016 3m read
Windows write caching

(This article was reviewed in February 2021. It is still relevant to Caché-based installations and similarly applies to IRIS-based installations.)

This article discusses the Windows write caching setting which can leave systems vulnerable to data loss or corruption in the event of power loss or operating system crash. The setting is on by default in some Windows configurations.

10 4
1 1.9K
Article
· Aug 26, 2016 8m read
Enterprise Monitor and HealthShare

Enterprise Monitor is a component of Ensemble and can help organizations monitor multiple productions running on different namespaces within the same instance or namespaces running on multiple instances.

Documentation can be found at:

http://docs.intersystems.com/ens20161/csp/docbook/DocBook.UI.Page.cls?KEY=EMONITOR_all#EMONITOR_enterprise

In Ensemble 2016.1 there were changes made to make this utility work with HealthShare environments.

This article will:

  • Show how to set up Enterprise Monitor for HealthShare sites
  • Show some features of Enterprise Monitor
  • Show some features of Enterprise Message Viewer

For this article, I used the following version of HealthShare:

Cache for Windows (x86-64) 2016.1 (Build 656U) Fri Mar 11 2016 17:42:42 EST [HealthShare Modules:Core:14.02.2415 + Linkage Engine:14.02.2415 + Patient Index:14.02.2415 + Clinical Viewer:14.02.2415 + Active Analytics:14.02.2415]

10 2
0 1.4K

Suppose you have developed your own app with InterSystems technologies stack and now want to perform multiple deployments on the customers' side. During the development process you've composed a detailed installation guide for your application, because you need to not only import classes, but also fine-tune the environment according to your needs.
To address this specific task, InterSystems has created a special tool called %Installer. Read on to find out how to use it.

16 9
4 4.1K

** Revised Feb-12, 2018

While this article is about InterSystems IRIS, it also applies to Caché, Ensemble, and HealthShare distributions.

Introduction

Memory is managed in pages. The default page size is 4KB on Linux systems. Red Hat Enterprise Linux 6, SUSE Linux Enterprise Server 11, and Oracle Linux 6 introduced a method to provide an increased page size in 2MB or 1GB sizes depending on system configuration know as HugePages.

At first HugePages required to be assigned at boot time, and if not managed or calculated appropriately could result in wasted resources. As a result various Linux distributions introduced Transparent HugePages with the 2.6.38 kernel as enabled by default. This was meant as a means to automate creating, managing, and using HugePages. Prior kernel versions may have this feature as well however may not be marked as [always] and potentially set to [madvise].

Transparent Huge Pages (THP) is a Linux memory management system that reduces the overhead of Translation Lookaside Buffer (TLB) lookups on machines with large amounts of memory by using larger memory pages. However in current Linux releases THP can only map individual process heap and stack space.

6 9
5 5K

Your application is deployed and everything is running fine. Great, hi-five! Then out of the blue the phone starts to ring off the hook – it’s users complaining that the application is sometimes ‘slow’. But what does that mean? Sometimes? What tools do you have and what statistics should you be looking at to find and resolve this slowness? Is your system infrastructure up to the task of the user load? What infrastructure design questions should you have asked before you went into production? How can you capacity plan for new hardware with confidence and without over-spec'ing? How can you stop the phone ringing? How could you have stopped it ringing in the first place?

23 13
5 4.4K

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.

9 7
2 2.7K

Here are a few examples of conversions and operations you might need, along with links to documentation where you can learn more.

At the time I wrote this, Eastern Daylight Time was in effect for my Caché system.

How Caché keeps the time and date

Caché has a simple time format, with a longer range of recognized dates compared to some other technologies.

The current time is maintained in a special variable $HOROLOG ($H):

8 4
0 14K
Question
· Oct 30, 2016
ISCAgent debug

Good day!
Is there an opportunity to debug the ISCAgent behaviour (in Linux)? ISCAgent uses /etc/iscagent/iscagent.conf as configuration file, but in docs I've found a description only for two parameters (port number and interface - http://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY=...). Other parameters I can see by running /usr/local/etc/cachesys/ISCAgentCtrl status:

1 8
0 2.5K

One of the topics that comes up often when managing Ensemble productions is disk space:

The database (the CACHE.DAT file) grows in a rate that was unexpected; or the Journal files build up at a fast pace; or the database grows continuously though the system has a scheduled purge of the Ensemble runtime data.

It would have been better if these kind of phenomena would have been observed and accounted for yet at the development and testing stage rather than on a live system.

For this purpose I created a basic framework that could aid in this task.

4 7
2 1.3K

This post provides further detail on the suggestions from the DeepSee Troubleshooting Guide about what to do if a user is not able to view a listing in a DeepSee cube, but instead sees errors like this:

ERROR #5540: SQLCODE: -99 Message: User <username> is not privileged for the operation [zfindStatement+118^%SQL.DynamicStatement.1:<namespace>] (8)

1 1
0 809

This week I am going to look at CPU, one of the primary hardware food groups :) A customer asked me to advise on the following scenario; Their production servers are approaching end of life and its time for a hardware refresh. They are also thinking of consolidating servers by virtualising and want to right-size capacity either bare-metal or virtualized. Today we will look at CPU, in later posts I will explain the approach for right-sizing other key food groups - memory and IO.

So the questions are:

14 10
2 4.8K

++ Update: August 1, 2018

The use of the InterSystems Virtual IP (VIP) address built-in to Caché database mirroring has certain limitations. In particular, it can only be used when mirror members reside the same network subnet. When multiple data centers are used, network subnets are not often “stretched” beyond the physical data center due to added network complexity (more detailed discussion here). For similar reasons, Virtual IP is often not usable when the database is hosted in the cloud.

Network traffic management appliances such as load balancers (physical or virtual) can be used to achieve the same level of transparency, presenting a single address to the client applications or devices. The network traffic manager automatically redirects clients to the current mirror primary’s real IP address. The automation is intended to meet the needs of both HA failover and DR promotion following a disaster.

14 12
4 5.9K

I'm pleased to see this in the documentation of the just-published 2017.1 Field Test of Ensemble:

"In certain circumstances, it is useful to create namespaces that are not enabled for Ensemble. In this release you can do this by clearing the Make this an Ensemble namespace checkbox when creating a new namespace. "

4 1
0 565

In the last post we scheduled 24-hour collections of performance metrics using pButtons. In this post we are going to be looking at a few of the key metrics that are being collected and how they relate to the underlying system hardware. We will also start to explore the relationship between Caché (or any of the InterSystems Data Platforms) metrics and system metrics. And how you can use these metrics to understand the daily beat rate of your systems and diagnose performance problems.

19 10
2 3.8K

Problem:

A file-based business service uses a local path on a Linux machine that is actually a mounted CIFS share. The mount is "soft" and is designed to not cache data, etc. There are times however when the remote system offering up the share (it's a Windows machine I believe) gets bounced or otherwise hung up the business service in the Ensemble production just hangs.

0 4
0 1.6K

Hi!

I am not system admin. But it used to be very simple to install CSP Gateway on an apache system on Linux with Apache installed. I used to run the CSP Gateway installation program and after it was done, all I had to do was fine tune some configurations on CSP Gateway portal on http://<ip>/csp/bin/Systems/Module.cxw and I was up and running.

0 5
0 1.3K

This post will show you an approach to size shared memory requirements for database applications running on InterSystems data platforms including global and routine buffers, gmheap, and locksize as well as some performance tips you should consider when configuring servers and when virtualizing Caché applications. As ever when I talk about Caché I mean all the data platform (Ensemble, HealthShare, iKnow and Caché).


A list of other posts in this series is here

29 3
7 10K

Hyper-Converged Infrastructure (HCI) solutions have been gaining traction for the last few years with the number of deployments now increasing rapidly. IT decision makers are considering HCI when scoping new deployments or hardware refreshes especially for applications already virtualised on VMware. Reasons for choosing HCI include; dealing with a single vendor, validated interoperability between all hardware and software components, high performance especially IO, simple scalability by addition of hosts, simplified deployment and simplified management.

9 7
1 3.4K