This reverts commit c252b1de.

* back fl

* delete ssl cert

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* make warning

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* unittest paral degree

* solve unittest

* heter & multi cloud commm ready

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* fix gloo compile warning

* adapt for nn fl-ps

* adapt lazy init and fix pass

* add unittest

* update comment

* fix amp and sharding

* remove clip_by_norm

* simplify size op

* trans to cuda manuly

* fix copy error

* support iterable dataset for auto parallel

* add split_data proto

* fix unittest bug

* fix recompute bug

* update cmake

* dist_matmul trans

* update unittest

* update cmakelist

* bugfix (#45332)

* customize wait_comm

* add fetch and prune for build cinn pass

* add prune flag

* config

* fix unittest

* zero init & cache & patch config

* add barrier to save and load

* add unittest

* bugfix (#45332)

* dist embedding support lookup table v1

* add unitest

* update unitest cmake

* add grad_clip pass

* add unittest

* add notes

* update func

* add dist_attr for new op

* back fl

* delete ssl cert

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* make warning

* .

* unittest paral degree

* solve unittest

* heter & multi cloud commm ready

* .

* .

* fl-ps v1.0

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* support N + N mode

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* .

* .

* .

* delete print

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* .

* .

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* fix bug

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* fl-ps with coordinator ready

* merge dev

* update message parse only

* update fl client scheduler

* fix bug

* update multithreads sync

* fix ci errors

* update role_maker.py

* update role_maker.py

* fix ci error: windows py import error

* fix ci error: windows py import error

* fix windows ci pylib import error

* add dump fields & params

* try to fix windows import fleet error

* fix ps FLAGS error

* fix logging risk

* fix logging possible risk

* write trainer_desc file

* support split sparse params in local & remote

* fix import paddle.fluid.core.PSGPU

* fix import paddle.fluid.core.PSGPU

* add remote_sparse & local_sparse config

* fix unittest

* fix test_dist_fleet_geo table error

* fix PADDLE_ENFORCE error

* fix other's pr conflict

* forbidden ssd table

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* recover ssd table code

* recover file mode

* support high order differential with data parallel overlap

* update unitest

* add quant pass

* bugfix

* remove scaling

* support rescale_grad opt

* add unitest

* rewrite get free port strategy

* hide the old one

* add clip_grad

* fix comments

* add unittest

* update logger