没想明白，还请大家帮忙解读下这个java gc日志

canyon

jdk1.5中，看日志基本1分钟fullgc一次，但是感觉没理解fullgc的原因是什么？参数配置有问题么？ 感谢大家指点了：

启动参数大致设置如下：
-server -Xmx2048m -Xms2048m -Xmn768m -Xss256k -XXermSize=256M -XX:MaxPermSize=256M -XX:+UseConcMarkSweepGC -XX:+UseCMSCompactAtFullCollection -XX:+UseParNewGC -XX:CMSMaxAbortablePrecleanTime=5


4.740: [Full GC 4.740: [CMS: 0K->1927K(1310720K), 0.3891269 secs] 62802K->1927K(2096448K), [CMS Perm : 11655K->11646K(262144K)], 0.3895953 secs]
51.950: [GC 51.950: [ParNew: 785024K->0K(785728K), 0.6023309 secs] 786951K->90477K(2096448K), 0.6027848 secs]
53.645: [GC 53.646: [ParNew: 785024K->0K(785728K), 0.0122148 secs] 875501K->90955K(2096448K), 0.0126495 secs]
54.665: [GC 54.665: [ParNew: 785024K->0K(785728K), 0.0074924 secs] 875979K->91398K(2096448K), 0.0079372 secs]
55.784: [GC 55.784: [ParNew: 785024K->0K(785728K), 0.0134618 secs] 876422K->92045K(2096448K), 0.0138974 secs]
56.862: [GC 56.862: [ParNew: 785024K->0K(785728K), 0.0099446 secs] 877069K->92326K(2096448K), 0.0103776 secs]
57.896: [GC 57.897: [ParNew: 785024K->0K(785728K), 0.0103202 secs] 877350K->92592K(2096448K), 0.0107368 secs]
59.004: [GC 59.005: [ParNew: 785024K->0K(785728K), 0.0146693 secs] 877616K->93199K(2096448K), 0.0151128 secs]
65.147: [Full GC 65.148: [CMS: 93199K->98721K(1310720K), 3.3502977 secs] 565194K->98721K(2096448K), [CMS Perm : 26167K->26114K(262144K)], 3.3510463 secs]
106.175: [GC 106.175: [ParNew: 785024K->0K(785728K), 0.2443760 secs] 883745K->118851K(2096448K), 0.2450444 secs]
125.753: [GC 125.753: [ParNew: 785012K->0K(785728K), 0.0315899 secs] 903863K->120966K(2096448K), 0.0322012 secs]
128.551: [Full GC 128.551: [CMS: 120966K->111111K(1310720K), 3.3155987 secs] 244516K->111111K(2096448K), [CMS Perm : 27272K->27252K(262144K)], 3.3162145 secs]
150.921: [GC 150.922: [ParNew: 785024K->0K(785728K), 0.0153722 secs] 896135K->113626K(2096448K), 0.0160100 secs]
169.518: [GC 169.519: [ParNew: 785024K->0K(785728K), 0.0189947 secs] 898650K->117246K(2096448K), 0.0196230 secs]
188.888: [GC 188.889: [ParNew: 785024K->0K(785728K), 0.0132184 secs] 902270K->119656K(2096448K), 0.0138335 secs]
191.926: [Full GC 191.926: [CMS: 119656K->111614K(1310720K), 3.3472774 secs] 243131K->111614K(2096448K), [CMS Perm : 27749K->27739K(262144K)], 3.3479202 secs]
245.108: [GC 245.108: [ParNew: 785024K->0K(785728K), 0.0158956 secs] 896638K->114131K(2096448K), 0.0165496 secs]
255.286: [Full GC 255.286: [CMS: 114131K->111188K(1310720K), 3.1354699 secs] 150980K->111188K(2096448K), [CMS Perm : 28101K->28088K(262144K)], 3.1360865 secs]
318.436: [Full GC 318.436: [CMS: 111188K->111159K(1310720K), 3.3122658 secs] 340986K->111159K(2096448K), [CMS Perm : 28115K->28107K(262144K)], 3.3129322 secs]
381.805: [Full GC 381.805: [CMS: 111159K->111326K(1310720K), 3.3333756 secs] 350247K->111326K(2096448K), [CMS Perm : 28143K->28133K(262144K)], 3.3340589 secs]
445.142: [Full GC 445.143: [CMS: 111326K->111248K(1310720K), 2.7684535 secs] 340138K->111248K(2096448K), [CMS Perm : 28164K->28154K(262144K)], 2.7690981 secs]
507.922: [Full GC 507.923: [CMS: 111248K->111291K(1310720K), 2.6704914 secs] 304969K->111291K(2096448K), [CMS Perm : 28171K->28163K(262144K)], 2.6711512 secs]
570.607: [Full GC 570.607: [CMS: 111291K->111585K(1310720K), 3.4155509 secs] 370997K->111585K(2096448K), [CMS Perm : 28242K->28235K(262144K)], 3.4162324 secs]
607.702: [GC 607.702: [ParNew: 785024K->0K(785728K), 0.0141068 secs] 896609K->112932K(2096448K), 0.0147750 secs]
634.071: [Full GC 634.071: [CMS: 112932K->111597K(1310720K), 3.6583704 secs] 568481K->111597K(2096448K), [CMS Perm : 28298K->28286K(262144K)], 3.6591689 secs]
697.781: [Full GC 697.782: [CMS: 111597K->111770K(1310720K), 3.5219246 secs] 477758K->111770K(2096448K), [CMS Perm : 28328K->28315K(262144K)], 3.5226215 secs]
761.317: [Full GC 761.318: [CMS: 111770K->111360K(1310720K), 2.7489994 secs] 285419K->111360K(2096448K), [CMS Perm : 28331K->28321K(262144K)], 2.7496724 secs]
824.130: [Full GC 824.130: [CMS: 111360K->111499K(1310720K), 2.7060421 secs] 305589K->111499K(2096448K), [CMS Perm : 28335K->28327K(262144K)], 2.7067542 secs]
886.920: [Full GC 886.921: [CMS: 111499K->111853K(1310720K), 2.7895009 secs] 324975K->111853K(2096448K), [CMS Perm : 28362K->28352K(262144K)], 2.7901777 secs]
949.727: [Full GC 949.728: [CMS: 111853K->111826K(1310720K), 2.7028269 secs] 308019K->111826K(2096448K), [CMS Perm : 28365K->28358K(262144K)], 2.7034946 secs]
1012.500: [Full GC 1012.500: [CMS: 111826K->111870K(1310720K), 2.9328143 secs] 439647K->111870K(2096448K), [CMS Perm : 28373K->28362K(262144K)], 2.9334805 secs]
1075.481: [Full GC 1075.481: [CMS: 111870K->111950K(1310720K), 2.7101106 secs] 304701K->111950K(2096448K), [CMS Perm : 28377K->28369K(262144K)], 2.7107889 secs]
1138.211: [Full GC 1138.211: [CMS: 111950K->112141K(1310720K), 2.7661311 secs] 302933K->112141K(2096448K), [CMS Perm : 28381K->28371K(262144K)], 2.7667879 secs]
1200.991: [Full GC 1200.991: [CMS: 112141K->112094K(1310720K), 2.6907942 secs] 290150K->112094K(2096448K), [CMS Perm : 28394K->28387K(262144K)], 2.6915016 secs]
1263.775: [Full GC 1263.775: [CMS: 112094K->112208K(1310720K), 2.7698457 secs] 319105K->112208K(2096448K), [CMS Perm : 28413K->28403K(262144K)], 2.7705346 secs]
1326.561: [Full GC 1326.561: [CMS: 112208K->112220K(1310720K), 2.7904834 secs] 317436K->112220K(2096448K), [CMS Perm : 28423K->28413K(262144K)], 2.7911541 secs]
1389.371: [Full GC 1389.371: [CMS: 112220K->112570K(1310720K), 2.9495763 secs] 442333K->112570K(2096448K), [CMS Perm : 28434K->28423K(262144K)], 2.9502970 secs]
1452.374: [Full GC 1452.374: [CMS: 112570K->112527K(1310720K), 2.8658968 secs] 373042K->112527K(2096448K), [CMS Perm : 28447K->28436K(262144K)], 2.8666338 secs]
1509.508: [GC 1509.508: [ParNew: 785024K->0K(785728K), 0.0143714 secs] 897551K->114170K(2096448K), 0.0150457 secs]
1515.308: [Full GC 1515.308: [CMS: 114170K->112523K(1310720K), 2.7107842 secs] 219819K->112523K(2096448K), [CMS Perm : 28459K->28449K(262144K)], 2.7114511 secs]
1578.106: [Full GC 1578.106: [CMS: 112523K->112637K(1310720K), 3.0348983 secs] 511068K->112637K(2096448K), [CMS Perm : 28483K->28472K(262144K)], 3.0356572 secs]
1641.161: [Full GC 1641.161: [CMS: 112637K->112584K(1310720K), 2.7126445 secs] 288553K->112584K(2096448K), [CMS Perm : 28484K->28475K(262144K)], 2.7133088 secs]
1703.924: [Full GC 1703.925: [CMS: 112584K->112498K(1310720K), 3.3900357 secs] 303947K->112498K(2096448K), [CMS Perm : 28490K->28479K(262144K)], 3.3907054 secs]
1767.405: [Full GC 1767.406: [CMS: 112498K->112612K(1310720K), 2.7950040 secs] 301227K->112612K(2096448K), [CMS Perm : 28488K->28480K(262144K)], 2.7956945 secs]
1830.253: [Full GC 1830.253: [CMS: 112612K->112869K(1310720K), 2.7914825 secs] 312485K->112869K(2096448K), [CMS Perm : 28493K->28485K(262144K)], 2.7921579 secs]

zjilvufe

感觉Xmn768m，太小。查下代码，是否有大量局部变量。