我使用Grails与MongoDB进行交互，主要用于域验证。在进行数十万条记录的批量更新时，我的内存不足（超出GC开销限制）。我已经解决了在域对象上使用findBy的问题。如果我用等效的GMongo.DB.collection.findOne替换那个DomainClass.findByProperty，我没有内存问题。
批量更新是在一个事务中（静态事务=＆＃39; mongo＆＃39;）但是用完了一个运行脚本。
我经常尝试刷新并清除会话，但无济于事。我一点一点地耗尽了记忆。这仅在使用GORM时发生。
// This is will fail after a while
// def cust = Customer.findByCustomerNo (custno, [ cache: false ]) ?: new Customer ()
// This will work but if I follow it by a get it will fail after a while
def found = mongodbService.DB.customers.findOne (customerNo: custno)
def cust = (found) ? Customer.get ("${found._id}") : new Customer ()
这是我经历的一种退化，我使用的是Grails 2.5.0和mongodb-3.0.3。
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