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This might be a little more of a satisfactory answer. The problem was solved by initialising a Spatial function that calls a CLR assembly. After that the query works. I know that that was the issue because when I restore the database in question the problem comes back and the solution is as described above. I can call any spatial function that calls a CLR ...


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The "memory" being referred to in the term "memory pressure" is physical RAM, not hard-drive space. What exactly are you attempting to do when you get this error? It seems that it could be due to attempting to invoke CLR code from within an sp_OA* OLE-Automation stored procedure call. That is documented in the following Microsoft forum thread: CLR ...


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You are running MySQL 5.7 with PHP on the one server. This shows me that your server is not dedicated to MySQL. PHP and MySQL are evidently competing for RAM. I also do not see any attempt to set the InnoDB buffer pool size. The default value for innodb_buffer_pool_size is 128M (134217728). Please keep in mind something about max_allowed_packet. As the ...


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It's almost certainly going to be full backups or indexing. The queries won't show up as a bunch of memory allocated but rather as intensive disk IO. If you are tracking those counters then have a look. Some other easy ways to confirm that these are the cause of that disk IO: Looking at agent job schedules. If it wasn't checkdb, or indexing, then apps ...


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Before you say PLE is too low, you should know threshold calculation for PLE. You can visit the URL to know that http://sqlperformance.com/2014/10/sql-performance/knee-jerk-page-life-expectancy. PLE alone don't impact performance of SQL server. There are various performance counter we should consider like Buffer cache hit ratio, disk queue length, ...


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Unfortunately PLE alone isn't going to tell you much. What's your baseline PLE? Does it dip then steadily rise again, or does it stay low for an extended amount of time? Are you getting any performance hits? My advice would be to build up a bigger picture of the issue by looking at other memory related performance measures. Page Life Expectancy is just ...


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NUMA is not unrelated to buffer pool preallocation. That is the reason why innodb_buffer_pool_populate was introduced in the first place. See https://blog.jcole.us/2012/04/16/a-brief-update-on-numa-and-mysql/ That is also the reason why it took around 7-8 minutes to start mysql with the older Percona release. Now the upstream implementation replaced ...


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Apart from Existing answers,you will need to know how RAM is utilised by SQL Server. Suppose you have a box with 100 GB RAM dedicated for SQL Server only.SQL Server will utilise all this RAM until you constrain it and lets say you constrain SQL Server maximum memory to 94 GB... Lets understand how this 94GB memory is used and what are the main components ...


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even though I have 100gb of ram memory. What version and edition of SQL Server are you using? 2012 (and earlier) standard edition will only use up to 64Gb so if you are using those there is little point adding more memory in this situation. Even in later releases the limit is 128Gb for standard edition. Of course if you are running enterprise then such ...


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Every time you scan a big index (or a big table, if you prefer) that data has to be brought from disk to memory. When this happens, if the buffer pool is holding data from other objects and does not have enough free space to accomodate the pages you are reading from disk, something has to be discarded. Low PLE means that this process happens too often, ...


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According to release docs innodb_buffer_pool_populate was mapped to innodb_numa_interleave starting with Percona 5.6.27-75.0, so based on what you see, it appears it is no longer preallocating the buffer pool, only setting the numa policy. Regarding innodb_buffer_pool_dump_at_shutdown and load at startup, you might want to have a look at http://dev.mysql.com/...


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While waiting to hear back on a few questions that I posted in a comment on the Question, I will at least reiterate one of my questions: "What about your current stats leads you to suspect that SQLCLR usage is in any way related to performance issues?" From what I see of your output, SQLCLR is taking up very little memory. It has 110 MB of physical ram for ...


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As dezso mentioned in the question comments, this did seem to be an issue with (possibly more recent versions of the) 3.13 kernel in Ubuntu Trusty - we switched to the Xenial HWE 4.4 kernel in Trusty and the problem seems to have gone away and compaction stalls are now very small and don't interfere.


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In 1GB of RAM, you may be able to set innodb_buffer_pool_size to 50M, maybe 100M. But definitely not 800M. The 80% advice is predicated on having at least 4GB of RAM, and 80% is too high even for that. Having other things on the same machine (Apache?) adds to the cramped quarters. If you have Apache, lower MaxClients to 10. Other things to keep out of ...


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Case 1: An extra table or database will eventually be pushed out of cache. It is harmless. Cure (but not worth doing): restart mysqld. Case 2: The 'system' is building thousands of tables and/or databases. Each table/database involves at least one entry in the containing OS directory. As this directory gets fuller, the OS operations to access files/...


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sp_helpdevice does list all allocated fragments on a device when you specify the device name. This includes the size of each fragment, but indeed not the free/used metrics. Those would not be difficult to write yourself however.



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