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Answer from user1472187 will work, but unfortunately these settings won’t last a reboot. You need to add some init scripts: http://frank2.net/cgroups-ubuntu-14-04/ Shell script is available for Ubuntu 14.04: http://brainsuckerna.blogspot.com.by/2016/05/limiting-mongodb-memory-usage-with.html


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Grrr. Neither of the answers so far quite says the right things, so I feel obligated to give yet another Answer. @jkavalik gives a nice description of why the problem occurred. (But not what to do next.) @DaveRix starts out good by saying "use RAM for caches, not RAM disk". I very much agree. But then he goes on to advocate dangerously high values for ...


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Personally, I'd be allocating more RAM to MySQL itself rather than the RAM disk, and then putting the tmp store on physical media. MySQL works much better when it has more memory allocated to things such as buffers and the innodb cache. Also make sure your max_heap_size and tmp_table_size variables are set to as high as they can be (64Mb), so that the ...


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Temp is used to store temporary on-disk tables for queries which go over the in-memory tmp tables limit. When MySQL needs to insert to a table and there is not enough space, the query stops - You get disk-full warning and you can either free some space or kill the offending query. In your case one runaway query would probably stop all queries using on-disk ...


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To start with I must say you have set max server memory to 6 GB and total memory is 8 GB so you have just left 2 GB for the OS, which in many cases, even if nothing is installed apart from SQL Server on a Windows machine, is too little memory provided to OS. To function properly, on a system with antivirus installed, OS must be given 4 GB at least. I leave ...


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SQL Server uses many more Caches other than the Buffer Cache although that is by far and away the biggest (an obvious example is the plan cache). You can take a closer look at memory through DBCC MEMORYSTATUS and a variety of DMVs. Target memory and total memory refer specifically to the Buffer Pool/ Cache. Excerpt from Christian Bolton's seminal ...


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The counter Memory Manager: Free Memory (KB) tells you below. Read the BOL document Free Memory (KB): Specifies the amount of committed memory currently not used by the server. So what this means is of all committed memory SQL Server is not using 40 MB of the memory. This is not telling you free memory on the SQL Server system. A committed memory is ...


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Your memory is cached. System is consuming it, not MySQL. On your top image: Mem: 8177776k total, 8039108k used, 138668k free, 600888k buffers, 5138768k cached This may be caused by intensive I/O, for example. See this answer for details and some explanation.


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Just going by the MySQL Documentation, I would say yes. According to the MySQL 5.6 Documentation on innodb_adaptive_hash_index Disabling the adaptive hash index empties the hash table immediately. Normal operations can continue while the hash table is emptied, and executing queries that were using the hash table access the index B-trees directly ...


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You can probably do a thousand simple commands on a MEMORY table per second. Can you, the single user, type fast enough to exceed that?? If you can, InnoDB may be the answer. In at least one test, high speed ingestion worked better with InnoDB, presumably because of the differences in locking. Be aware that data varchar(64000) NULL is not efficient in ...


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You said in your question It makes me think that when you insert/update/replace the table locks itself automatically and entirely so you will not be able to select anything while the write is being done. Is this correct? You are correct. The MEMORY storage engine performs a full table lock for every DML statement. That is why the link you mentioned ...


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If you are running on Linux, you can use control groups to limit MongoDB memory as shown in the following article: Easy Steps to Limit Mongodb Memory Usage by Ramakanta Sahoo On Windows, a similar technique using the Windows System Resource Manager is described in: Limit MongoDB memory use on Windows without Virtualization by Simon Green


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Thanks for your answer. I have checked the connections on both servers. But the results are strange. On the Master DB server there are more connections than on the slave: Master netstat | grep TIME_WAIT | wc -l 148 htop mysql VIRT 44G RES 34,7G Slave netstat | grep TIME_WAIT | wc -l 78 htop mysql VIRT 174G RES 68G


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You should not be using MySQL 5.6.20 at all. Why ? I wrote this post back on Nov 14, 2014 : Find MySQL Patch Level where I had just found out about Oracle's Security Patch. My company had upgraded to 5.6.20. To our horror, the security patch then came out of nowhere. We had to redeploy MySQL Installation in puppet to upgrade to 5.6.21. I still need a ...



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