informix的最大历史连接数

[oioft]

informix的master库中sysshmvals表中
的sh_ovlmaxcons是不是只有重装数据库才能让它变小？

[帝企鹅已被占用]

嗯，你说的对，是server被建立以来的。
Interesting undocumented table –
Sysshmvals*
sh_mode int, turbo mode number
sh_boottime int, boot time of day
sh_pfclrtime int, time profilers were last clr
sh_curtime int, current mt_time
sh_bootstamp int, boot time stamp
sh_stamp int, current time stamp
sh_mainlooptcb int, address of main daemon thread
sh_sysflags int, system operating flags
sh_maxchunks int, size of chunk table
sh_maxdbspaces int, size of dbspace table
sh_maxuserthreads int, max # of user structures
sh_maxtrans int, max # of trans structures
sh_maxlocks int, # of locks total
sh_maxlogs int, size of log table
sh_nbuffs int, # of buffers total
sh_pagesize int, buffer size in bytes
sh_nlrus int, # of lru queues
sh_maxdirty float,LRU can have this % dirty pages
sh_mindirty float,LRU has % dirty pages after clean
sh_ncleaners int, # of cleaning/flushing procs
sh_longtx int, the long transaction flag
sh_optstgbsnum int, Subsystem Staging Blobspace
sh_cpflag int, TRUE => doing checkpoint
sh_rapages int, Number of pages to read ahead
sh_rathreshold int, When to start next read ahead
sh_lastlogfreed int, last log (id) written to tape
sh_rmdlktout int, max timeout when distributed
sh_narchivers int, number of active archives
sh_maxpdqpriority int, max pdqpriority
sh_fuzcpflag int, fuzzy checkpoint flag
sh_needcpsync int, hard checkpoint
sh_nfuzzy int, # buffers marked fuzzy
sh_nfuzzyprev int, # buffers marked fuzzy in last ckpt
sh_oldestlsnuq int, lsn of oldest update not
sh_oldestlsnpos int, flushed to disk
sh_builddpt int, builing DPT necessary
sh_ndptentries int, #entries in DPT
sh_dptsize int, size of DPT
sh_curmaxcons int, max #connections in this run
sh_ovlmaxcons int max #connections since server init

[oioft]

那就是只能重装数据库，才能让那个值变小？

[帝企鹅已被占用]

不知道你要那个数清零有什么目的。
感觉上是那个instance 的问题，和数据库没关系

[帝企鹅已被占用]

好像是server start的时间，重启应该会变小。

[oioft]

sh_ovlmaxcons这个是历史最大连接数
重启只能让sh_curmaxcons（当前最大连接数）变为1

[bbgg]

我也碰到类似的问题/。
我在c++中用多线程方式连接informix数据库。
加上主线程，一共开了65个线程，每个线程单独连接数据库，并操作数据库表。
但是当超过65个时，线程也开不了，程序会异常。
查sysshmvals的sh_curmaxcons 字段也是这个数。

不知道大家编写多线程连informix的时候，遇到过这种问题没有？

[Mysap-gwg]

哈哈，关注一下。