Yes there is. What is this number? It depends.
If a specific service (like calculations service), is used in standalone web application mode, then we expose it to Tomcat without any alteration. Tomcat by default allows 200 concurrent (worker) threads. (Can be changed by server.tomcat.threads.max property. Be aware it also has a maximum number for accepted connections which is 8192, and can be changed by server.tomcat.max-connections property.) But this is also influenced by the OS settings and the available memory. (A process can not sprout endless threads.)
If the service is used in microservices system mode then our gateway service have hystrix circuit breaker installed which only allows 10 running threads and 90 waiting requests. These of course can be configured. For configuration detail please find our documentation or the hystrix's documentation. It is generally better to scale up the waiting requests rather than active ones since too many active tasks can cause throttling. If they have to scale, it is better to scale out the number of executing nodes and load balance the requests.
If the client runs a service in production for many users he is better off with many small requests than few huge ones. If the service is for a very few (even one) individual then few huge requests (with many structures) can have a performance benefit. It must be told: after a certain size the performance gain will be negligible. The number of ideal structures are also influenced by the requested method, and the "size" of the structures (and even the size of the structure representation, a.k.a. the chemical format). As a general rule of thumb I can say: requests should not take longer than 1 seconds. 1-2000 molecules can be a good number for that (but it depends). If a request takes more than 1 second it is more costly to experience any kind of error and it also limits the number of concurrent requests. In one second the total communication cost is less than 1% of the whole process, if you move beyond that it is meaningless.
It is configurable. The default configuration using h2 db, but you can change it to PostgreSQL as well. See configuration details here.
If your JChem Microservices DB configuration is using h2 backend, then it is possible to configure the service to access the embedded h2 db console. You need to add the following lines to application.properties file:
spring.h2.console.enabled=true spring.h2.console.path=/h2 spring.h2.console.settings.web-allow-others=true
After restarting the service the database console is available at the localhost's 8062 port. http://localhost:8062/h2
Logging parameters are configured in the application.properties file. The default values are:
It is supported through external beans with introduction of a new logic (filter, endpoint, filter, logging, health check, etc.). An example is available here.
In the case molecule types with tautomerHandlingMode=GENERIC parameter, similarity search gives false results. These is no workaround at the moment, please do not execute similarity search in table having molecule type with com.chemaxon.zetor.types[n].tautomerHandlingMode=GENERIC parameter specified in the application.properties file.
If the default schema gcrdb is set in the application.properties file, the additional parameters - taken from JChem Engines cache and memory calculator like com.chemaxon.zetor.settings.molecule.cachedObjectCount are not taken into account. If you want to set these additional parameters, please set com.chemaxon.zetor.settings.scheme= mapdb