...el since then, but it nicely explains the reason why mmap or read might be faster or slower. A call to mmap has more overhead than read (just like epoll has more overhead than poll, which has more overhead than read). Changing virtual memory mappings is a quite expensive operation on some process...

...刷新的物化视图如“create materialized view mv_tablename refresh fast on demand start with sysdate next sysdate+1/288 as select * from T_tablename@dblink_name;”。 现在，数据库A上此表的主键约束因主键字段值重复而被disable了，在第三个数据库C上新建这个...

...ntract of an object, the object may throw this exception... Note that fail-fast behavior cannot be guaranteed as it is, generally speaking, impossible to make any hard guarantees in the presence of unsynchronized concurrent modification. Fail-fast operations throw ConcurrentModificationException on ...

...ncoming changes. The git pull command is safe so long as it only performs fast-forward merges. If git pull is configured to only do fast-forward merges and when a fast-forward merge isn't possible, then Git will exit with an error. This will give you an opportunity to study the incoming commits, ...

...and then a few nested Ext grids. Everything was actually rendering pretty fast, no single operation took a long time, there was just a lot of information being rendered all at once, so it felt slow to the user. We 'fixed' this, not by switching to a faster component, or optimizing some method, b...

... Very interesting that sorted list has FASTER lookup than hashtable. I thought hashtable is O(1) vs sorted list O(logn). Apparently hashtable sucks. I'll never use it. – John Henckel Jan 10 at 14:32 ...

...red ;memory storage allocation. opcache.revalidate_freq=60 ;If enabled, a fast shutdown sequence is used for the accelerated code ;The fast shutdown sequence doesn't free each allocated block, but lets ;the Zend Engine Memory Manager do the work. opcache.fast_shutdown=1 ;Enables the OPcache for th...

... It depends on the problem. Adjacency Matrix Uses O(n^2) memory It is fast to lookup and check for presence or absence of a specific edge between any two nodes O(1) It is slow to iterate over all edges It is slow to add/delete a node; a complex operation O(n^2) It is fast to add a new edge O(...

...ome tests with the OP's code and made some changes. I actually got D going faster for LDC/clang++, operating on the assumption that arrays must be allocated dynamically (xs and associated scalars). See below for some numbers. Questions for the OP Is it intentional that the same seed be used for ea...

...ge-load. Bots request a page, parse the page and submit the form. This is fast. Humans type in a URL, load the page, wait before the page is fully loaded, scroll down, read content, decide wether to comment/fill in the form, require time to fill in the form, and submit. The difference in time can...