Survey Results on Real-Time OS Use Trends and ITRON

1. Outline of the Survey

A questionnaire similar to the one distributed the previous year was used to survey how the ITRON-specification OS is being put to use and what the users think of this OS architecture, as well as determining the kinds of ITRON-related activities people would like to see carried out. The results were then analyzed. A summary of the survey results follows.

• Results of last year's survey (survey period: Nov. 1996 - Jan. 1997)

1.1 Survey period

The survey was conducted from November 1997 through January 1998.

1.2 Survey methods and number of responses

(1) How the survey was carried out

Questionnaires were distributed by the following means, then were collected and the answers were tabulated.

• Sent by direct mail
• Distributed at trade fairs on embedded systems

The survey forms were distributed mainly in Japan, and these results were tabulated and analyzed.

(2) Number distributed and responses

Of the questionnaires distributed by the above means, 438 responses were received. The number of questionnaires and responses of each kind are as follows.

	Distributed	Responses	Response rate
Direct mail	1,145	277	24.2%
Trade fair handouts	811	161	19.9%

The response rate for questionnaires distributed by direct mail was close to the 25% registered the year before.

Learning from earlier experience, the method of distributing questionnaires at trade fairs was improved over the previous year, resulting in a much better response rate than the 6.4% a year ago and approaching the direct mail rate.

This year the survey was not conducted on the Internet.

Surveyed population and survey items

Because of the nature of the survey, the questions were directed primarily at developers of embedded systems, who are either users or potential users of a real-time OS. The main items surveyed are as follows.

(1) Recently developed embedded systems

The survey asked about the application fields, system scale and real-time OS used in the three embedded systems most recently developed by the respondent.

(2) Difficulties with real-time OSs and basis for selection

(3) Awareness of ITRON-specification OS and related activities, etc.

(4) Advantages and disadvantages of an ITRON-specification OS

Persons using, developing or investigating the use of an ITRON-specification OS were asked about its advantages and disadvantages.

(5) Wishes for the ITRON subproject

1.4 Occupations of the respondents

About 85% of the respondents said they were in design or development, which means the survey reached its target audience.

2. Analysis of Survey Results

2.1 Recently developed embedded systems

The respondents were asked about the application fields, CPU size, program size, and real-time OS used in the case of the three embedded systems most recently developed by them or their company.

The response rates indicated below for each of the questions is in relation to the total number of embedded systems.

(1) Application fields of recently developed embedded systems

Consumer-oriented products (home appliances, audio/visual, entertainment and education, personal information appliance, and communication equipment (terminal) accounted for around 30 percent of the total, and industrial equipment (plant control, factory automation, electric equipment) accounted for more than 40 percent, with the remaining 25 percent going to other kinds of industrial systems. These can be seen as appropriate results when it is considered that they represent the number of systems developed, not the number produced, given that consumer products tend to be produced in large volumes but the number of different systems is not so large.

* The respondents are asked to select an application field by referring to this table.

(2) CPU used in recently developed embedded systems

In recently developed embedded systems, 32-bit CPUs occupied the largest share at around 48 percent, followed in order by 16-bit and 8-bit models, indicating that 32-bit processors have become the mainstream choice even in the embedded control field. Use of 64-bit processors is still very rare, and 4-bit chips accounted for a mere 1 percent of the total.

It should be noted, however, that these results are likely skewed somewhat toward high-end processors for the following reasons, and do not exactly mirror the actual picture overall. For one thing, the survey asked respondents to choose up to three of the most recently developed systems; and in a survey on a real-time OS, the tendency would be to choose systems of a scale that would likely use a real-time OS. Also, if one system uses several processors, the responses concern only the main processor, so that in fact, 4-bit processors are probably in wider use than these results suggest.

(3) Program size in recently developed embedded systems

Program sizes this year as last were divided rather evenly into the four categories of less than 64 KB, 64 KB to 256 KB, 256 KB to 1 MB, and 1 MB or more. That a quarter of the systems had a program size of 1 MB or more attests to the growing scale of embedded software. This is a trend that bears close watching in subsequent surveys.

The graph comparing program size to the size of the CPU confirms the trend toward using larger programs with the more powerful CPUs.

In systems using 32-bit CPUs, which were the majority, more than 40 percent had a program size of 1 MB or more, indicating again the trend toward large-scale embedded systems. Still, a quarter of these systems used programs of 256 KB or less, showing that a significant number of systems were able to keep the program size small even with powerful processors.

(4) Programming languages used for recently developed embedded systems

This question was included in the survey for the first time. If only one language was used for all three systems, that language was marked as "1"; if more than one, the others were ranked as "2" and "3" in order of the degree of use. In the table and graph below, the results for "single answer" are given as the percentage of all "1" answers, while the figures for "multiple answers" are in relation to the "1," "2" and "3" answers for each language.

Among the languages written in under "Other," PL/M and Visual Basic appeared a number of times.

(5) OS used in recently developed embedded systems

The overall trend in OS use this time shows that 25.0 percent of the systems reported on use no OS, 28.7 percent use an ITRON-specification OS (broken down to 16.4 percent commercial ITRON-specification OS and 12.3 percent in-house ITRON-specification OS), 17.6 percent use an original in-house OS, and 26.0 percent of the systems use a non-ITRON commercial OS. Of the systems that use an OS, a third use an ITRON-specification OS; and of the commercial OSs used, around 36 percent are ITRON-specification OSs.

Among the non-ITRON commercial OSs used, the share of Microsoft OSs (MS-DOS, Windows, etc.) is up from the previous year to 10.4 percent. The other figures are 4.1 percent for Wind River Systems products (VxWorks, etc.), 2.4 percent for Integrated Systems (ISI) OSs (pSOS, etc.), 2.2 percent for the CTRON-specification OS, and 1.5 percent each for Accelerated Technology OSs such as Nucleus Plus and for Microware Systems OSs such as OS-9. All other OSs were less than 1 percent each.

The questionnaire this time asked respondents choosing "OS not used" to indicate whether the reason is "Not necessary" or "Due to problems". The answer "Not necessary" was selected in 70 percent of the cases.

Looking at the relation of CPU scale to OS used, the following trends can be seen. First of all, there were no examples of OS use with a 4-bit processor. Around 40 percent of 8-bit systems use an OS, of which approximately half (20 percent of 8-bit systems) use an in-house original and a fifth (a twelfth of the total) use an ITRON-specification OS. Of 16-bit systems, around 30 percent use no OS and another 20 percent use in-house original OSs, these two categories making up half the total.

When it comes to 32-bit systems, just under 10 percent use no OS and around 15 percent use an in-house original OS. They are less than a quarter of the total. In spite of this difference, the rate of ITRON-specification OS use for both 16-bit and 32-bit systems is more than 30 percent, showing the wide use of the ITRON-specification OS regardless of CPU size. The difference between 16-bit and 32-bit systems in the ratio of systems that use no OS or an in-house original OS corresponds to the difference in the use ratio of other commercial OSs.

Program size relates to OS use as follows. Of systems with a program size of less than 64 KB, more than half do not use an OS and 20 percent use an in-house original OS. This trend closely matches that of 8-bit CPUs. In all other cases the rate of ITRON-specification OS use is around 30 percent, showing that the use of an ITRON-specification OS is not dependent on program size. In the case of in-house original OSs (with the exception of program sizes smaller than 64 KB), the use rate tends to go down as program size goes up. The percentage of systems with no OS goes down as program size increases, and in turn the rate of other commercial OS use goes up. Of systems with a program size of 1 MB or larger, 43 percent use a non-ITRON commercial OS.

Finally, the relation of application field to OS use was analyzed. The graph arranges applications in the order of ITRON-specification OS use, in descending order. Some application fields have only a small sample size (the basis for determining the ratio of use); but the general trend shown here is that ITRON-specification OSs are used especially in consumer-oriented systems (the categories personal information appliances, communication equipment (terminals), audio/visual equipment, and home appliances). The wide use of ITRON-specification OSs in consumer products is seen in these results.

In each of the categories of electric equipment, communication equipment (network equipment), personal computer peripheral/office equipment, and industrial control/factory automation, ITRON-specification OSs are widely used, in from 25 to 35 percent of the systems. When the share of the CTRON-specification OS is added the total is near 50 percent. Commercial OSs other than ITRON have a high use rate in personal information appliances and in the industrial equipment fields including industrial control/factory automation. In the field of transportation-related systems, where the ITRON-specification OS has the lowest use rate, the share of in-house OSs has dropped since the previous year's survey while that of other commercial OSs has risen.

2.2 Real-Time OS difficulties and selection criteria

All the survey subjects were presented lists of possible difficulties with using a real-time OS and of OS selection criteria, from which they were asked to choose the most important item or items (ranking them in order if they chose more than one). If they chose "Other" they could write in any other problems or criteria. The meaning of "single answer" and "multiple answers" is the same as in 2.1 (4) above.

The response percentages for these questions were figured using the number of respondents as the population size.

(1) Difficulties with using a real-time OS

The answer chosen most often as a problem with real-time OS use was "An absence or shortage of staff familiar with the technology." Nearly half the respondents chose this as a problem and 27.5 percent selected it as the most important problem.

In the single-response totals, the next most common difficulties selected were "Lack of a development environment and tools" and "Cost is too high," each of which were chosen by more than 10 percent of the respondents. "Major differences in OS specifications, making it hard to switch," "Performance and functions do not meet our requirements," and "OS size or resources used are too large" each were chosen by approximately 8 percent of the respondents. Compared to the previous survey, "Lack of a development environment and tools" increased in weight this time.

Looking at multiple responses, "Lack of a development environment and tools" with around 36 percent of the total and "Cost is too high" at 30 percent are especially noteworthy. The issue of development environment and tools is not the biggest issue but is seen as the next in importance.

When those who chose "Lack of a development environment and tools" were asked to name the specific tools lacking, more than half listed tools for debugging. A common complaint was the lack of a task-aware debugger. Many respondents also listed in-circuit emulators and tools for performance evaluation and validation (including real-time performance validation). Other needs expressed in this connection included tools for support at the design and other upstream processes and tools running on a personal computer. Altogether the responses pretty much covered the range of tools for software development.

(2) Real-time OS selection criteria

In the single-answer results, the most important selection criterion was given as "Performance and functions match our requirements," chosen by 27% of the respondents. This was followed by "Has a proven track record in our company" and "Is widely used in the industry," both focusing on the history of OS adoption and together making up 29% of the total. Vendor support, by contrast, was listed by only 2 percent of the respondents. It would be interesting to find out whether this result means vendor support is not considered important or whether vendor support is adequate and not seen as an issue.

When multiple answers are considered, history of adoption receives less overall weight, with more weight on two criteria that are under 10 percent each in the single-response results, namely, "Good development environment and tool support" and "Low cost," which come in second and third.

Among the answers written in under "Other," one advantage listed rather often is that once developers have selected a CPU, they need not worry about making other choices.

2.3 Awareness of ITRON-specification OS and related activities

The response percentages for these questions were also figured using the number of respondents as the population size.

(1) Awareness of the ITRON-specification OS

The responses "Have used or developed an ITRON-specification OS" and "Have investigated or considered its use" together made up around two-thirds of the responses, whereas "Was not aware of ITRON" was selected by only 2 percent of the respondents, confirming the high degree of awareness of the ITRON specifications. The 40 percent response rate for "Have used or developed an ITRON-specification OS" would appear to be congruous with the ITRON-specification OS use rate of approximately 25 percent. As for those who responded "Have heard about ITRON," it will be necessary to carry out more intensive promotional efforts encouraging them to investigate and consider the ITRON specifications.

(2) Awareness of ITRON-related PR

The percentage of respondents who were aware of the ITRON Web site rose considerably from 26 percent on the last survey to 44 percent this time. Awareness of "Booths or presentations at trade shows and exhibitions" and the "ITRON Open Seminar" grew by around 5 percent. There was almost no increase in awareness of the ITRON Newsletter, the official PR vehicle of the ITRON Technical Committee, indicating that more must be done by way of promotion here.

(3) Awareness of ITRON-related committee and study group activities

The greater than 50 percent awareness of the ITRON Technical Committee can be considered the result of PR efforts over the years, but the level of awareness of the committees and study groups that have started their work since 1996 is still low at between 10 and 20 percent of respondents.

(4) Awareness of other ITRON-related activities

More than half of the respondents were aware of the µITRON3.0 specification itself, but far fewer knew about the µITRON3.0 compatibility check sheets or the Registration System for ITRON-specification Products provided by the ITRON Technical Committee. Awareness of the TRON Project Symposium, TRONSHOW and TRONWARE by which the TRON Project is publicized was at about the same level as in the last survey.

2.4 Advantages and disadvantages of the ITRON-specification OS

Those respondents who answered the question at 2.3 (1) by indicating that they have used, developed, investigated or considered the ITRON-specification OS were asked about the advantages and disadvantages of this OS. They were presented with a list of items and asked to pick the most important, marking it as "1," then mark the two next-most important, if any, as "2" and "3." The meaning of "single answer" and "multiple answers" is the same as in 2.1 (4) above.

The response percentages for these questions were figured using the number of respondents as the population size.

(1) ITRON-specification OS advantages

The graph of single-response results shows that "The specifications are easy to understand" and "Small OS size and resource use" each received more than 20 percent of the votes, indicating that the respondents have a clear understanding of the ITRON-specification OS advantages. The large number of respondents who chose "The specifications are easy to understand" in particular shows the success of the ITRON specification design policy that emphasizes engineer training. Many respondents also chose "Supports a wide range of chips," which indicates they appreciate that the ITRON specifications have been implemented on many different processors. Another oft-cited advantage was "Low cost." On the other hand, only a very small number of respondents picked "Good development environment and tools." These trends are similar for both single and multiple answer results.

(2) ITRON-specification OS disadvantages

In single-answer results, more than a quarter of the respondents chose "Lack of a development environment and tools" as the biggest disadvantage. This is somewhat fewer than in the previous survey, but reaffirms a problem that is often pointed out. Next in frequency was "No notable disadvantages," chosen by 16.2 percent of the respondents.

Looking at multiple-answer results, relatively high shares were received by "Lack of software components," "Lack of engineers familiar with it," and "Too many implementation-dependent parts making it hard to port," each of which was chosen in only ten percent of the single-answer results. The particularly high rate of response for "Lack of software components," newly added to the list of choices on this survey, shows that there is a strong demand for standardization to improve software portability and enable software components to be swapped in and out of systems.

Among the write-in responses, the low awareness of ITRON overseas was pointed out more than once.

2.5 Wishes for ITRON-related activities

The respondents were asked to select up to three areas in which they would most like the ITRON subproject to become involved. Of the single answers, around a quarter chose "Standardization of interfaces with development environments (esp. debuggers)," again showing the need for debugging support in OS development. In the multiple answer results, "Interface standards for software components" was chosen almost as often as "Standardization of interfaces with development environments" with both selected in more than 40 percent of the responses. These were followed by "C++ and Java language binding standards," "Free ITRON-specification OS," and "Network support" at around 24 percent each. The need for hard real-time support, being worked on by a currently active study group, was cited in only 10 percent of the responses. On the other hand, "Creation of application design guidelines," which is a subtheme of that study group, came in at 20 percent, suggesting that the issue of development methods using a real-time OS is a suitable topic for study.

The response percentages for these questions, too, were figured using the number of respondents as the population size.

There was space on the questionnaire for writing in additional requests and opinions on ITRON activities. The total number of such responses was small, making it difficult to discern any trends; but a number of respondents requested enhanced PR and advertising, development of a more compact OS specification, and the availability of programming samples to help beginners. There were also comments on JTRON, which was announced around the time of the survey.

3. Summary

The questionnaire was a partially modified version of that used for the previous survey. There were 50 percent more responses this time, making the results more statistically relevant. There were no major changes from the overall trends last time. An ITRON-specification OS was selected for a third of the systems that used an OS, far more than any other OS, reaffirming the status of this OS specification as an industry standard in Japan.

The results for advantages and disadvantages of the ITRON-specification OS were similar to those in the previous survey, with a very large number of respondents citing the inadequacy of the development environment and tools. The ITRON Technical Committee is aware of this issue and has begun to take steps to solve part of the problem. The results on ITRON awareness confirmed the high level of familiarity with the ITRON-specification OS itself, but insufficient awareness of related activities, showing the need for more effective promotional efforts.

The number of systems built without an OS was somewhat smaller than in the previous survey but still accounts for a quarter of all systems reported on. In small-scale systems the inability to employ an OS can be seen as unavoidable, but there are also large-scale systems in which no OS was used. This would indicate that more must be done to promote the spread of real-time OSs. One of the main reasons cited for not using an OS is the lack of skilled engineers, pointing to the importance of training engineers in the use of a real-time OS.

Reference

• Results of last year's survey (survey period: Nov. 1996 - Jan. 1997)
• Questionnaire Form on Real-Time OS Use Trends and ITRON (PDF)
• The Collection of the Charts (PDF)