![]() ![]() full GC (G1 usually occurs when there is a problem).G1 during operation mainly includes the following four operating modes: Want more controllable, predictable GC pause period prevent high concurrent applications under avalanche.It will generate a large amount of memory fragmentation during operation, requiring constant compression space.Server multicore CPU, JVM memory footprint larger applications (at least greater than 4G).G1 will be used in Young GC, whereas CMS can only be used in the O Zoneįor now, CMS GC policy choice or default, G1 may be more suitable in the following scenarios:.G1 immediately after the recovery of memory free memory consolidation while doing work, and the default CMS is doing STW (stop the world) when.G1 garbage collection time can be controlled to avoid application of the avalanche phenomenon by setting the expected pause time (Pause Time).Eden, Survivor, Old area is no longer fixed, more flexible and efficient use of memory on it.G1 memory space is divided into regions by (Region) way to avoid memory fragmentation issues.G1 has an advantage in terms of compression space.Usually work in most systems use CMS, even a silent upgrade to JDK7 default still use CMS, then the G1 relative to the difference in the CMS: This is why the reasons for the G1 Garbage First name: the first time to deal with the most garbage blocks. ![]() While cleaning up the blocks G1 still need to suspend application threads, but you can use relatively little recovery time priority contain up to block spam. This will O area is divided into a plurality of blocks from the idea: When a background thread concurrency looking for recyclable objects, some blocks contain recyclable objects a lot more than other blocks. Each region may belong to both the O region, there may be a region Y, and each type of space region may be discontinuous (CMS comparative O, and Y region area must be continuous). Unlike other generational collection algorithm, G1 will heap space being divided into separate blocks independent of one another. G1 GC is one of the new features Jdk7 of, Jdk7 + version can be self-configured G1 as the JVM GC option as JVM GC algorithm of a major upgrade, after DK7u G1 has been relatively stable, and future plans to replace CMS, it is necessary to understand the next : ![]() Link: http: /// depth understanding G1 garbage collector / ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |