* fix dump, fix cvm check
test=develop

* fix
test=develop

* fix
test=develop

* fix
test=develop

* split meta optimizer files
* add graph execution in execution, update two properties in DistributedStrategy, unit tests for these features

* add localsgd meta optimizer

* add pipeline optimizer

* Remove slim from paddle framework
test=develop
Co-authored-by: Nwanghaoshuang <wanghaoshuang@baidu.com>

* fix inverse bug, test=develop

* fix the untest, test=develop

* add singular checking, test=develop

* fix the utest, test=develop

* use memory::copy, test=develop

* fix bost_get, test=develop

* fix position, test=develop

* hidden the explicit setting of dataset for pipeline training.

* modify pipeline demo, test=develop

Update the code for the compare_ops, update the api and doc 

This reverts commit ab5a1fb8.

* fix test_pipeline, test=develop

* refine error stack format

* polish compile traceback format

* polish detail format

* add gradient Merge optimizer to meta, test=develop

Integrated Trainer of Parameter Server (API add `fluid.contrib.layers.sparse_embedding` only) (#22957)

* Integrated Trainer of Parameter Server

[Dy2Stat-ErrorMessage]  Add interface:create_origin_info_map and attach_origin_info for AST node (#25627)

* Add interface:create_origin_info_map and attach_origin_info for AST node. test=develop

* Fix code according to comments from reviewers. test=develop

* fix double grad visitid unit; test=develop

* change name hash_pair to HashPair; test=develop

* follow comment; test=develop

* reduce hidden size and loop number; test=develop

* change loop number; remove useless code; test=develop

Fix the argsort and sort op for the api2.0, and update the api 

* Remove the output for moving_average_abs_max_scale op, test=develop

* refine strategy compiler and meta optimizers
make async as a_sync

* remove ProgramTranslator.save_inference_model

* adapt save_quantized_model

* revert buffer check implemention

* remove useless import function

* simplify buffered reader to improve DataLoader performance

* fix 22 failed unittests

* fix cuda pinned context condition

* fix test_reader_reset failed

* fix two failed unittests

* change unittest place

* polish error messaage

* polish cast op GetExpecctedKernelType

* remove debug info in unittest

Enhance TracedLayer Error Message

Note: this PR uses assert to check type somewhere and check_type somewhere, the reason is that the check_type skips checking when it is under dygraph mode.

* saving inference model for user defined quantization model

* saving inference model for user defined quantization model

* fixed ci coverage

* add more settings for distributed strategy
Basically, DistributedStrategy has several parts of configurations:
- BuildStrategy: the same as paddle.fluid.BuildStrategy, but the distributed arguments are moved out of BuildStrategy
- ExecutionStrategy: the same as paddle.fluid.ExecutionStrategy
- collective communication configs: nccl_comm_num, hierarchical allreduce and so on
- distributed algorithms: async_update(mainly used in PS), lars, lamb and so on