## 4 StoRfm v2
### Example
#### 4.5.3 Ontology Example
\begin{table}
\begin{tabular}{|c|c|c|c|c|c|c|c|c|} \hline
**SOAP Statistics** & **Average** & **Standard** & **Standard** & **zLow** & **zHigh** & **Verb** & **Adapter** & **Significant** \\
**(all figures in msecs)** & & **Deviation** & **Error** & **95\%** & **95\%** & & +/- & **Value** \\  & & & & & & & & **95\%** \\  & & & & & & & & (+/- **1.645**) \\ \hline
**ServiceView** & no & 67 & 12.08 & 1.2 & 65 & 69 & POST & n/a & 3.45 \\  & adapter & & & & & & & \\ \cline{2-10}  & adapter & 72.11 & 8.54 & 0.85 & 70 & 74 & GET & +8\% & \\ \hline
**ServiceAdd** & no & 65.29 & 7.95 & 0.79 & 64 & 67 & POST & n/a & 2.23 \\  & adapter & & & & & & & \\ \cline{2-10}  & adapter & 68.98 & 14.48 & 1.44 & 66 & 72 & POST & 6\% & \\ \hline
**ServiceDelete** & no & 66.87 & 13.64 & 1.36 & 64 & 70 & POST & n/a & 3.39 \\  & adapter & & & & & & & \\ \cline{2-10}  & adapter & 72.22 & 7.85 & 0.78 & 71 & 74 & DELETE & +8\% & \\ \hline
**ServiceUpdate** & no & 65.46 & 7.65 & 0.76 & 64 & 67 & POST & n/a & 2.67 \\  & adapter & & & & & & & \\ \cline{2-10}  & adapter & 67.84 & 4.52 & 0.45 & 67 & 69 & PUT & +4\% & \\ \hline \end{tabular}
\end{table} 
Table 1: Internet Adapter statistics. these SOAP requests via the adapter to their RESTful Web Service equivalents is significantly longer (statistically) than the average time taken to issue these requests directly to the SOAP Server. ### Linear Regression Analysis

The adapter behaves consistently when mapping to PUT/POST _i.e._, the message body is copied from the incoming SOAP request to the outgoing RESTful request. However, this is not the case with GET/DELETE, where parsing of the incoming SOAP message is required to populate the RESTful URI. The example SOAP files used in the requests to create Table 1 were based on sample files used in industry. All the files were 1643 bytes in size. In addition, these files required the adapter to perform very little parsing when mapping to a GET or DELETE (the adapter had to evaluate 2 XPath expressions). Therefore, further tests were required and undertaken in order to measure whether or not the penalty imposed by the adapter when mapping to GET/DELETE is a function of:

* the size of the SOAP request file and/or
* the amount of parsing to be conducted by the adapter

Size of SOAP request file

Figure 11 below represents test results where the request file size is increased steadily for 15 iterations in an environment where there is no adapter in situ _i.e._, the requests travel directly to the server. All response times are based of averages of 100 requests. As Figure 11 demonstrates, the response times increase as and when the request file sizes increase. The correlation value between the size of the request files and the response times is 0.936. Thus, as one would expect, when requests travel directly to the server, there is a strong correlation between the size of the request files and the response times. Figure 12 represents the graph where the exact same requests are issued with the adapter in situ _i.e._, the requests travel to the server via the adapter. The requests map to a GET and in order to isolate the file size impact, the parsing requirement remains constant across the requests (2 XPath expressions to be evaluated as in Table 1). Figure 11: Performance–increasing file sizes, static parsing, no adapter. The correlation value between the size of the request file and the response time when the adapter is in place is -0.276. Thus, there is a very weak linear relationship between the size of the request file and the response time taken when requests travel via the adapter. If we fitted the least squares line to the data the equation would be:

\[\text{Time}=-3/10000\ \times\text{file size}+79.35\]

The extremely weak correlation value is demonstrated by the linear regression equation. The response time is almost entirely dependent on the constant. Thus, the file size has virtually no bearing on the response times.