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ASF GitHub Bot commented on TRAFODION-2478: ------------------------------------------- Github user zellerh commented on a diff in the pull request: https://github.com/apache/incubator-trafodion/pull/953#discussion_r100863353 --- Diff: core/sql/cli/memorymonitor.cpp --- @@ -102,12 +102,18 @@ MemoryMonitor::MemoryMonitor(Lng32 windowSize, { // if the windowSize is 0, we do not need memory monitor. assert(windowSize); - char buffer[1024]; + char buffer[2048]; char *currPtr; size_t bytesRead; fd_meminfo_ = fopen("/proc/meminfo", "r"); if (fd_meminfo_) { - bytesRead = fread(buffer, 1, 1024, fd_meminfo_); + bytesRead = fread(buffer, 1, 2048, fd_meminfo_); + if (ferror(fd_meminfo_)) + assert(false); --- End diff -- Could you remind me what this assert would do? Would it just write a log entry or would it kill the process and cause a core dump? I would say we shouldn't cause a failure of the process. > Reduce the number of memory monitoring threads in Trafodion SQL processes > --------------------------------------------------------------------------- > > Key: TRAFODION-2478 > URL: https://issues.apache.org/jira/browse/TRAFODION-2478 > Project: Apache Trafodion > Issue Type: Improvement > Components: sql-exe > Affects Versions: any > Reporter: Selvaganesan Govindarajan > Assignee: Selvaganesan Govindarajan > > A memory monitor thread is created in every SQL process to handle the memory > pressure in BMO (Big memory operators). This has following drawbacks: > 1) No consistent view of the memory pressure in the node > 2) Overhead of calculating the memory pressure in every trafodion SQL process. > Proposal is to move this thread to RMS SSCP process. All SQL processes have > access to RMS shared segment. Hence SQL processes can get the view of the > memory pressure readily and easily from the shared segment. > It is also possible to increase the frequency of the memory pressure > calculation to get near real tiime picture of the memory pressure. -- This message was sent by Atlassian JIRA (v6.3.15#6346)