App Engine查询根据appstats忽略batch_size？

Question

我正在运行批量大小为1000的查询

self.model.all().run(batch_size=1000)

然而，在app stats中，查询列出了多个读取，批量大小为300：

@68ms datastore_v3.RunQuery real=48ms api=0ms cost=21070 billed_ops=[DATASTORE_READ:301]
@338ms datastore_v3.Next real=217ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@851ms datastore_v3.Next real=193ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@1323ms datastore_v3.Next real=128ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@1739ms datastore_v3.Next real=200ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@2214ms datastore_v3.Next real=139ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@2641ms datastore_v3.Next real=199ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@3121ms datastore_v3.Next real=210ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@3628ms datastore_v3.Next real=198ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@4149ms datastore_v3.Next real=202ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@4724ms datastore_v3.Next real=203ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@5222ms datastore_v3.Next real=202ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@5652ms datastore_v3.Next real=266ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@6139ms datastore_v3.Next real=196ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]
@6627ms datastore_v3.Next real=202ms api=0ms cost=21000 billed_ops=[DATASTORE_READ:300]

批次数与批量300相匹配。

为什么忽略batch_size设置？