## 3 Results  
Table 3 presents examples of building CDM servers and DBs in various infrastructures for CDM data from Seoul St. Mary's Hospital, Yeouido St. Mary's Hospital, and St. Vincent in Korea for each purpose, as well as applying the formula in Table 2. An example of the DA type is a case in which both a DB and an AP server are built on a personal desktop by collecting data from 1000 patients out of the entire Seoul St. Mary's CDM database as an example. An example of the OLTP type is a case in which both DB and AP servers are built on the Amazon cloud server by collecting data from patients with eight diseases (non-small cell lung cancer, non-Hodgkin lymphoma, dyslipidemia, hypertension, type 2 diabetes mellitus, ischemic stroke, Alzheimer's disease, and rheumatoid arthritis) of Seoul St. Mary's Hospital. An example of the DW type is a case in which all CDM data from Seoul St. Mary, Yeouido St. Mary, and St. Vincent Hospital are extracted, and the DB server is built on the physical server, and the AP server is built on another cloud server and constructed with a separated design. Table 4 presents TPS, average latency, 90 th percentile latency, and maximum latency parameters according to the scale for each DB type. Scale factor refers to the size of the DB that multiplies the default size of DB. TPS decreased as scale increased in all DB types; however, average, 90 th percentile, and maximum latencies exhibited no tendency according to scale. Table 5 presents TPS, average latency, 90 th percentile latency, and maximum latency parameters according to clients by DB type. The value of the client is the number of \begin{table}
\begin{tabular}{l c c c} \hline \hline  & **DA** & **OLTP** & **DW** \\ \hline Data source & CDM 1000 sample data & Eight disease-related data & All data from Seoul \\  & per table from Seoul & from Seoul St. hospital & St. hospital, Yeouido \\  & St. hospital & & St. Hospital, and \\  & & & St. Vincent hospital \\ Number of Patient Data & 1000 & 131,411 & 7,956,745 \\ DB Size & 12 GB & 76 GB & 634 GB \\ Number of Servers & One & One & Two \\ Server Format & Physical Desktop & Cloud Server & Physical Server \\ \hline Server Design & Combined & Combined & Separated \\ \hline Memory & 32 GB & 8 GB & 128 GB \\ shared\_buffers & 2 GB & 2 GB & 32 GB \\ effective\_cache\_size & 8 GB & 6 GB & 96 GB \\ work\_mem & RAM (GB)/6/MC & RAM (GB)/MC & RAM (GB)/2/MC \\ maintenance\_work\_mem & 2 GB & 500 MB & 2 GB \\ \hline Storage & SSD & SSD & HDD \\ random\_page\_cost & 1.1 & 1.1 & 4.0 \\ effective\_io\_concurrency & 200 & 200 & 2 \\ \hline Query and Connection & & & \\ default\_statistics\_target & 100 & 100 & 500 \\ max\_connections & 15 & 30 & 20 \\ Write-Ahead Logging & & & \\ min\_wal\_size & 100 MB & 2 GB & 4 GB \\ max\_wal\_size & 2 GB & 8 GB & 16 GB \\ checkpoint\_completion\_target & 0.5 & 0.9 & 0.9 \\ wal\_buffers & 6 MB & 6 MB & 16 MB \\ Worker Processes & & & \\ max\_worker\_processes & 20 & 36 & 16 \\ max\_parallel\_workers\_per\_gather & 4 & 4 & 8 \\ max\_parallel\_workers & 20 & 36 & 16 \\ max\_parallel\_maintenance\_workers & 4 & 4 & 4 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Examples of applying DB configuration parameter tuning recommendations in actual scenarios. concurrent accesses to the DB. The maximum number of clients was set by subtracting 10 from max_connection for each DB type in Table 3, and the test was performed by dividing it into 5 parts. When the number of clients was the same in all DB types (client = 1, 5), the TPS, average latency, 90 th percentile latency, and maximum latency values of each DB type were also similar. When comparing the max values of each client (DA client = 5, OLTP clients = 20, DW clients = 10), the TPS, average latency, 90 th percentile latency, and maximum latency values were highest in the order of OLTP, DW, and DA. Table 6 presents the results obtained from measuring the virtual memory status (vmstat) for 1 min during the test runtime.