I suspect your Supermicros are broken one way or the other – possibly the battery packs are overheating. Most recent LSIs would report the temperature through MegaCLI – you might want to monitor this value on servers which needed replacement. root@host:~/SOLARIS# ./MegaCli -AdpBbuCmd -GetBbuStatus -aALL BBU status for Adapter: 0 BatteryType: BBU […] Temperature: 41 … Read more
No, there’s not a way to force a database into cache, unfortunately. Your brute force method is probably the most straightforward. You might be able to get closer by using index defrag scripts with a very low threshold setting, like saying rebuild the index if it’s 1% fragmented, like this: http://sqlserverpedia.com/wiki/Index_Maintenance It’ll take longer and … Read more
Embedded Variables, $realpath_root: an absolute pathname corresponding to the root or alias directive’s value for the current request, with all symbolic links resolved to real paths The solution of using $realpath_root instead of $document_root is copy-pasted all around the Q/A sites and forums; it is actually hard to avoid finding it.Yet, I’ve only seen it … Read more
Yes. Your ISP is almost certainly caching DNS settings for some period of time. They are supposed to refresh the records when the TTL expires. Unfortunately there are a large number of ISPs that seem to ignore TTLs all together in their DNS caching schemes. If you happen to be on one of those ISPs … Read more
Generally speaking, in direct answer to your question, I am not aware of any major brands of SATA drives that the drive itself has had bugs relative to proper operation with write caching enabled. That is, from a drive perspective only, the drive does what it is supposed to do from a caching perspective. I … Read more
How about this: net session \\samba.server.ip.address /delete You can also use: net use To give a list of active sessions and to ensure that you’ve deleted them afterwards.
Clearing caches will hinder performance, not help. If the RAM was needed for something else it would be used by something else so all you are doing is reducing the cache hit/miss ratio for a while after you’ve performed the clear. If the data in cache is very out of date (i.e. it is stuff … Read more
You didn’t tell NGINX for how much time the response is valid and must be served from cache. This must be specified with proxy_cache_valid directive. proxy_cache one; proxy_cache_key $host$uri$is_args$args; proxy_cache_valid 200 10m; But, this won’t work for POST requests because you have no cache key that differs from a POST request to another on the … Read more
… unless we do a full refresh (clear cache) from our browser. This in itself, a clear manifestation that the “problem” is on the client-side. sendfile has nothing to do with caching, only how NGINX buffers / reads the file (trying to stuff the contents directly into the network “slot”, or buffer its contents first). … Read more
You can develop your own SystemTap script. You need to account the following two subsystems: VFS: this represents all I/O requests before the Buffer cache (i.e. absolutely every I/O request); review the “vfs.read”, “vfs.write” and the “kernel.function(“vfs_*”)” probes; you need to filter out the block devices you want to monitor by their respective major+minor numbers. … Read more