Wire compression causes sporadic "Error reading data from the connection." errors. ----------------------------------------------------------------------------------
Key: CORE-6468 URL: http://tracker.firebirdsql.org/browse/CORE-6468 Project: Firebird Core Issue Type: Bug Components: Engine Affects Versions: 3.0.7 Environment: Firebird 3.0.7, Windows 10 Reporter: michalk1 Attachments: TestCase.zip I came across this problem infrequently since first FB 3 versions. Now I finally found that it is related to WireCompression and was able to create a relatively reproducible test case. It consists of a repeated run of a long sql statement, with commits between them. It is easier to spot the error when the test is run concurrently from more consoles. Steps to reproduce: 1) Make a copy of a employee.fdb (or any other database) database, for example to "C:\Tmp\employee.fdb". 2) Modify firebird.conf to enable client wire compression (WireCompression = true). 3) Unzip test case script files (TestMain.sql and TestCmd.sql), say to "C:\Tmp\". TestCmd.sql is the command itself followed by a commit, TestMain.sql is there just to call it repeatedly. 3) Run several command line consoles (two should be enough), and in each of them, execute the sql script in isql: isql -user SYSDBA -password masterkey localhost:C:\Tmp\employee.fdb -i "C:\Tmp\TestMain.sql" 4) Sooner or later in some of the consoles (you may run the script repeatedly of from more consoles) you should spot the errors. The first one is always "Error reading data from the connection.". Following "Error writing data from the connection." are just consequence of the already dropped connection. Clues: - Disabling wire compression results in no errors at all. - Short sql statement are less likely to be affected, may be there is even a threshold under which the error doesn't occur. Contents of the long sql statement probably doesn't matter, just it's length. - When the error arises, other connections continue to run (at least for some time), which means that the problem is not caused by a server crash. It is just the single connection that drops out. - So far i couldn't reproduce the problem against Linux server, it may be Windows specific. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://tracker.firebirdsql.org/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel