Don't dump pages which only contain zero bytes #2331

simonis · 2024-01-15T14:55:25Z

I want to propose a new command line option zero-pages which, if enabled, detects pages which only contain zero bytes and skip their dumping to the image file. At restore, such pages will be replaced by the kernels zero page automatically.This can be useful for runtimes like Java, which often allocate large memory regions without fully using them (e.g. for the heap). For a simple Helloworld Java program, this new feature shrinks the image size be about 20% from 13mb to 11mb.

I've enabled GitHub Actions on my fork and all the test are green except the Alpine test which I see failing on upstream as well and the Code Linter test where I can't understand what he's objecting.

I'm a first time contributor to this project so please let me know if I've missed something.

Change made through this commit: - Include copy of flog as a seperate tree. - Modify the makefile to add and compile flog code. Signed-off-by: prakritigoyal19 <[email protected]>

CID 302713 (checkpoint-restore#1 of 1): Missing varargs init or cleanup (VARARGS) va_end was not called for argptr. Signed-off-by: Adrian Reber <[email protected]>

Separate commit for easier criu-dev <-> master transfer. Acked-by: Mike Rapoport <[email protected]> Signed-off-by: Adrian Reber <[email protected]>

It is mapped, not maped. Same applies for mmap I guess. Found by codespell, except it wants to change it to mapped, which will make it less specific. Signed-off-by: Kir Kolyshkin <[email protected]>

Brought to you by codespell -w (using codespell v2.1.0). [v2: use "make indent" on the result] Signed-off-by: Kir Kolyshkin <[email protected]>

Fixes: checkpoint-restore#2121 Signed-off-by: Pengda Yang <[email protected]>

The TOS(type of service) field in the ip header allows you specify the priority of the socket data. Signed-off-by: Suraj Shirvankar <[email protected]>

Signed-off-by: Suraj Shirvankar <[email protected]>

The pipe_size type is unsigned int, when the fcntl call fails and return -1, it will cause a negative rollover problem. Signed-off-by: zhoujie <[email protected]>

Newer Intel CPUs (Sapphire Rapids) have a much larger xsave area than before. Looking at older CPUs I see 2440 bytes. # cpuid -1 -l 0xd -s 0 ... bytes required by XSAVE/XRSTOR area = 0x00000988 (2440) On newer CPUs (Sapphire Rapids) it grows to 11008 bytes. # cpuid -1 -l 0xd -s 0 ... bytes required by XSAVE/XRSTOR area = 0x00002b00 (11008) This increase the xsave area from one page to four pages. Without this patch the fpu03 test fails, with this patch it works again. Signed-off-by: Adrian Reber <[email protected]>

Signed-off-by: Adrian Reber <[email protected]>

Using the fact that we know criu_pid and criu is a parent of restored process we can create pidfile with pid on caller pidns level. We need to move mount namespace creation to child so that criu-ns can see caller pidns proc. Signed-off-by: Pavel Tikhomirov <[email protected]>

By default, the file name 'amdgpu_plugin.txt' is used also as the name for the corresponding man page (`man amdgpu_plugin`). However, when this man page is installed system-wide it would be more appropriate to have a prefix 'criu-' (e.g., `man criu-amdgpu-plugin`). Signed-off-by: Radostin Stoyanov <[email protected]>

crun wants to set empty_ns and this interface is missing from the library. This adds it to libcriu. Signed-off-by: Adrian Reber <[email protected]>

--criu-binary argument provides a way to supply the CRIU binary location to run_criu(). Related to: checkpoint-restore#1909 Signed-off-by: Dhanuka Warusadura <[email protected]>

These changes remove and update the changes introduced in 7177938 in favor of the Python version in CI. os.waitstatus_to_exitcode() function appeared in Python 3.9 Related to: checkpoint-restore#1909 Signed-off-by: Dhanuka Warusadura <[email protected]>

These changes add test implementations for criu-ns script. Fixes: checkpoint-restore#1909 Signed-off-by: Dhanuka Warusadura <[email protected]>

These changes fix the `ImportError: No module named pathlib` error when executing criu-ns tests located at criu/test/others/criu-ns Signed-off-by: Dhanuka Warusadura <[email protected]>

CentOS 7 CI environment uses Python 2. To execute criu-ns script in CentOS 7 changing the current shebang line to python is required. This reverse the changes made in a15a63f Signed-off-by: Dhanuka Warusadura <[email protected]>

This is a patch proposed by Thomas here: https://lore.kernel.org/all/87ilczc7d9.ffs@tglx/ It removes (created id > desired id) "sanity" check and adds proper checking that ids start at zero and increment by one each time when we create/delete a posix timer. First purpose of it is to fix infinite looping in create_posix_timers on old pre 3.11 kernels. Second purpose is to allow kernel interface of creating posix timers with desired id change from iterating with predictable next id to just setting next id directly. And at the same time removing predictable next id so that criu with this patch would not get to infinite loop in create_posix_timers if this happens. Thanks a lot to Thomas! Signed-off-by: Pavel Tikhomirov <[email protected]>

This hook allows to start image streamer process from an action script. Signed-off-by: Radostin Stoyanov <[email protected]>

…tions This does cgroup namespace creation separately from joining task cgroups. This makes the code more logical, because creating cgroup namespace also involves joining cgroups but these cgroups can be different to task's cgroups as they are cgroup namespace roots (cgns_prefix), and mixing all of them together may lead to misunderstanding. Another positive thing is that we consolidate !item->parent checks in one place in restore_task_with_children. Signed-off-by: Valeriy Vdovin <[email protected]> Signed-off-by: Pavel Tikhomirov <[email protected]>

4.15-based kernels don't allow F_*SEAL for memfds created with MFD_HUGETLB. Since seals are not possible in this case, fake F_GETSEALS result as if it was queried for a non-sealing-enabled memfd. Signed-off-by: Michał Mirosław <[email protected]>

Linux 4.15 doesn't like empty string for cgroup2 mount options. Pass NULL then to satisfy the kernel check. Log the options for easier debugging. Signed-off-by: Michał Mirosław <[email protected]>

The original commit added saving THP_DISABLED flag value, but missed restoring it. There is restoring code, but used only when --lazy_pages mode is enabled. Restore the prctl flag always. While at it, rename the `has_thp_enabled` -> `!thp_disabled` for consistency. Fixes: bbbd597 (2017-06-28 "mem: add dump state of THP_DISABLED prctl") Signed-off-by: Michał Mirosław <[email protected]>

If prctl(SET_THP_DISABLE) is not used due to bad semantics, log it for easier debugging. Signed-off-by: Michał Mirosław <[email protected]>

While at it, don't carry over stale errno to the fail() message. Signed-off-by: Michał Mirosław <[email protected]>

Signed-off-by: Michał Mirosław <[email protected]>

Add a sanity check for THP_DISABLE. This discovered a broken commit in Google's kernel tree. Signed-off-by: Michał Mirosław <[email protected]>

adrianreber · 2024-01-16T16:06:31Z

I think the code linter wants a \n at the end of the warning.

Without looking too closely, the idea of this PR sounds like a good one.

simonis · 2024-01-16T16:25:32Z

I think the code linter wants a \n at the end of the warning.

Thanks, I've fixed that now.

Without looking too closely, the idea of this PR sounds like a good one.

Thanks.

criu/crtools.c

criu/mem.c

criu/include/cr_options.h

criu/config.c

When iptables-nft is used as backend for iptables, the rules for network locking are translated into the following nft rules: ``` $ iptables-restore-translate -f lock.txt add table ip filter add chain ip filter CRIU insert rule ip filter INPUT counter jump CRIU insert rule ip filter OUTPUT counter jump CRIU add rule ip filter CRIU mark 0xc114 counter accept add rule ip filter CRIU counter drop ``` These rules create the following chains: ``` table ip filter { # handle 1 chain CRIU { # handle 1 meta mark 0x0000c114 counter packets 16 bytes 890 accept # handle 6 counter packets 1 bytes 60 drop # handle 7 meta mark 0x0000c114 counter packets 0 bytes 0 accept # handle 8 counter packets 0 bytes 0 drop # handle 9 } chain INPUT { # handle 2 type filter hook input priority filter; policy accept; counter packets 8 bytes 445 jump CRIU # handle 3 counter packets 0 bytes 0 jump CRIU # handle 10 } chain OUTPUT { # handle 4 type filter hook output priority filter; policy accept; counter packets 9 bytes 505 jump CRIU # handle 5 counter packets 0 bytes 0 jump CRIU # handle 11 } } ``` In order to delete the CRIU chain, we need to first delete all four jump targets. Otherwise, `-X CRIU` would fail with the following error: iptables-restore v1.8.10 (nf_tables): line 5: CHAIN_DEL failed (Resource busy): chain CRIU Reported-by: Andrei Vagin <[email protected]> Signed-off-by: Radostin Stoyanov <[email protected]>

nft does not support xtables compat expressions https://git.netfilter.org/nftables/commit/?id=79195a8cc9e9d9cf2d17165bf07ac4cc9d55539f Signed-off-by: Radostin Stoyanov <[email protected]>

Show appropriate error messages when restore of nftables fails. Signed-off-by: Radostin Stoyanov <[email protected]>

criu/mem.c

rst0git · 2024-01-19T14:36:39Z

Code Linter test where I can't understand what he's objecting

@simonis Would it be possible to run make indent before committing your changes? This should fix the code style problems such as missing spaces. In addition, it would be great if you can add a commit message with a description that explains what changes are introduced and why. The following blog post describes how to write good commit messages: https://cbea.ms/git-commit/

test/javaTests/test-zero.xml

avagin · 2024-01-21T04:04:48Z

criu/mem.c

+		if (should_dump_page(vma->e, at[pfn])) {
+			if (opts.skip_zero_pages) {
+				remote[0].iov_base = (void*)vaddr;
+				nread = process_vm_readv(item->pid->real, local, 1, remote, 1, 0);


I don't like the idea to read process memory twice. We have to avoid this.

btw: #2292 solves the same problem in a more optimal way.

I agree that it would be better if we can avoid reading process memory twice.

#2292 solves the same problem in a more optimal way.

I think this is different. In #2292, we exclude pages with zero PFN (PAGE_IS_PFNZERO), while this option skips zero-filled memory (e.g., memory that has been filled with zeros using memset() would be skipped with this option).

Is this just a performance or a correctness issue? If it's just about performance, I think the benefit might justify the additional overhead and after all the feature is on by default.

In the case this is a correctness problem, do you have a suggestion how we can avoid this?

PS: and yes, @rst0git is right - this change is about skipping regular pages which are filled with only zero bytes.

This can be useful for runtimes like Java, which often allocate large memory regions without fully using them (e.g. for the heap). For a simple Helloworld Java program, this new feature shrinks the image size be about 20% from 13mb to 11mb.

we exclude pages with zero PFN (PAGE_IS_PFNZERO), while this option skips zero-filled memory

I believe we need a zdtm test, which can reproduce such a zero page without PAGE_IS_PFNZERO but with zero data. Maybe, we even want to fix kernel to report such a page as "PAGE_IS_PFNZERO" instead.

I agree with Andrei that manually checking page content with memcmp is an anti-pattern. Nack from me, at list in current state.

I also agree. Reading a page second time and using memcmp() sounds not optimal.

I still like the idea of not including empty pages in the checkpoint, but it sounds difficult.

If the kernel could track it, that would be nice. Not sure the kernel has a better alternative than memcmp() to find a zeroed memory page.

At this point I think it would be nice to see some numbers. How much faster is restoring if something like this PR is applied. Although I don't like the memcmp() it would only be used if the corresponding command-line option is explicitly selected by the user. Maybe that makes it acceptable. Can the second reading of the page be avoided?

Maybe some post-processing of the checkpoint image would be an alternative. Remove the empty pages after checkpointing and have support during restore to handle pages like this.

Is this just a performance or a correctness issue? If it's just about performance, I think the benefit might justify the additional overhead and after all the feature is on by default.

I don't understand why we need to read process pages to do this check? Why can't we do that before dumping these pages into the image (page_xfer_dump_pages)?

I believe memset(0) is used in specific scenarios where applications/libraries are dealing with sensitive data and/or use custom memory management.

It's not just the "malloc+memset(0)" use case. Java does mmap and pretouch memory so we can have a lot of pages with only zero content (but not the kernel zero page) in some scenarios.

First, I thought it does not work, upd: that was stupid of me not to enable --skip-zero-pages, with option it works fine, sorry.

Second, If Java put so much effort to have those zeroed pages in RSS isn't it a bad idea to restore those pages like they are "PAGE_IS_PFNZERO" ones? =)

[root@turmoil tmp]# ./malloc-test Enter any char to stop ------ In another terminal ------ [root@turmoil snorch]# grep 2097164 -A3 -B1 /proc/$(pidof malloc-test)/smaps 7fb87b744000-7fb8fb747000 rw-p 00000000 00:00 0 Size: 2097164 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Rss: 2097160 kB [root@turmoil tmp]# /home/snorch/devel/ms/criu/criu/criu dump --skip-zero-pages -v4 -o dump.log -t $(pidof malloc-test) -j -D /images-dir/ [root@turmoil tmp]# /home/snorch/devel/ms/criu/criu/criu restore -j -D /images-dir/ ------ In another terminal ------ [root@turmoil snorch]# grep 2097164 -A3 -B1 /proc/$(pidof malloc-test)/smaps 7fb87b744000-7fb8fb747000 rw-p 00000000 00:00 0 Size: 2097164 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Rss: 1048584 kB

upd2: If we want to preserve them in RSS, we can remember those special zero-filled pages in images on dump without saving their data and then on restore put them to RSS by writing zeroes.

Second, If Java put so much effort to have those zeroed pages in RSS isn't it a bad idea to restore those pages like they are "PAGE_IS_PFNZERO" ones? =)

@Snorch, Java (or OpenJDK based JVMs to be more specific) was not designed and optimized for cloud/container use cases but rather for large, monolithic application servers. In the old days, pretouching/zeroing memory was a way to pre-allocate physical memory and not potentially get it from swap later. For current cloud/container use cases the huge memory footprint can be problem. With check-pointing, a small image is more important and COWing a PAGE_IS_PFNZERO page is much faster then loading and populating it from disk.

I don't understand why we need to read process pages to do this check? Why can't we do that before dumping these pages into the image (page_xfer_dump_pages)?

Thanks a lot for your suggestion @avagin. I'm short of time for the next week because of FOSDEM/Jfokus but I'll try to come up with a new version which moves the zero check to page_xfer_dump_pages() afterwards.

@simonis FOSDEM was my favorite conference when I lived close by. btw @mihalicyn are there too, he is one of criu maintainers. He will be happy to help with any questions.

PAGEMAP_SCAN is a new ioctl that allows to get page attributes in a more effeciant way than reading pagemap files. Signed-off-by: Andrei Vagin <[email protected]>

Signed-off-by: Andrei Vagin <[email protected]>

This change adds a new injectable fault (135) to disable PAGEMAP_SCAN and fault back to read pagemap files. Signed-off-by: Andrei Vagin <[email protected]>

simonis · 2024-01-22T12:57:19Z

Code Linter test where I can't understand what he's objecting

@simonis Would it be possible to run make indent before committing your changes? This should fix the code style problems such as missing spaces. In addition, it would be great if you can add a commit message with a description that explains what changes are introduced and why. The following blog post describes how to write good commit messages: https://cbea.ms/git-commit/

Done (had to install a newer version of clang-format).

simonis · 2024-01-24T16:48:33Z

I believe we need a zdtm test, which can reproduce such a zero page without PAGE_IS_PFNZERO but with zero data.

I've now added a new zdtm test which verifies that the --skip-zero-pages option does indeed optimize pages which only contain zero bytes.

Introduces a new command line option '--skip-zero-bytes' which detects pages which only contain zero bytes and prohibits that they get dumped in the processes image file. It is a potentially expensive operation because it checks for every single process page if it contains only zeros, but it can significantly decrease the image size and improve the startup-time if many such pages exist. It effectively replaces such pages which the kernel's zero-page on restore. Signed-off-by: Volker Simonis <[email protected]>

rst0git · 2024-01-31T13:02:21Z

test/zdtm.py

@@ -2697,6 +2701,9 @@ def get_cli_args():
    rp.add_argument("--noauto-dedup",
                    help="Manual deduplicate images on iterations",
                    action='store_true')
+    rp.add_argument("--skip-zero-pages",


@simonis Would you be able to also enable testing with existing ZDTM tests using --skip-zero-pages in run-ci-tests.sh?

@simonis It was great meeting you at FOSDEM and your talk was very good!

We can use something like the following patch to run the existing ZDTM tests with --skip-zero-pages: rst0git@45a8ca1

@avagin Thank you for the review! Would it be sufficient to run the following tests?

diff --git a/scripts/ci/run-ci-tests.sh b/scripts/ci/run-ci-tests.sh index ef7e869e0..8f5e25d03 100755 --- a/scripts/ci/run-ci-tests.sh +++ b/scripts/ci/run-ci-tests.sh @@ -268,6 +268,9 @@ make -C test/others/rpc/ run ./test/zdtm.py run -t zdtm/transition/maps007 --pre 2 --page-server --dedup ./test/zdtm.py run -t zdtm/transition/maps007 --pre 2 --pre-dump-mode read +# Run tests with --skip-zero-pages +./test/zdtm.py run --skip-zero-pages -T '.*maps0.*' + ./test/zdtm.py run -t zdtm/transition/pid_reuse --pre 2 # start time based pid reuse detection ./test/zdtm.py run -t zdtm/transition/pidfd_store_sk --rpc --pre 2 # pidfd based pid reuse detection

rppt · 2024-02-03T09:48:21Z

\On Thu, Feb 1, 2024 at 9:47 PM Andrei Vagin ***@***.***> wrote:

@avagin commented on this pull request. ________________________________ In criu/mem.c: > vaddr = vma->e->start + *off + pfn * PAGE_SIZE; + /* + * If should_dump_page() returns true, it means the page is in the dumpees resident memory + * (i.e. bit 63 of the page frame number 'at[pfn]' is set) but it is not the zero-page. + */ + if (should_dump_page(vma->e, at[pfn])) { + if (opts.skip_zero_pages) { + remote[0].iov_base = (void*)vaddr; + nread = process_vm_readv(item->pid->real, local, 1, remote, 1, 0); @simonis FOSDEM was my favorite conference when I lived close by. btw @mihalicyn are there too, he is one of criu maintainers. He will be happy to help with any questions.

Both @mihalicyn and @rst0git are in the Containers devroom

…

-- Sincerely yours, Mike.

github-actions · 2024-03-08T00:38:14Z

A friendly reminder that this PR had no activity for 30 days.

simonis · 2024-03-08T09:14:14Z

Still on my ToDo list, so post this to avoid auto-closing..

prakritigoyal19 and others added 30 commits June 11, 2023 23:30

Add flog to CRIU

823db1b

Change made through this commit: - Include copy of flog as a seperate tree. - Modify the makefile to add and compile flog code. Signed-off-by: prakritigoyal19 <[email protected]>

flog: Missing varargs init or cleanup (VARARGS)

1444b72

CID 302713 (checkpoint-restore#1 of 1): Missing varargs init or cleanup (VARARGS) va_end was not called for argptr. Signed-off-by: Adrian Reber <[email protected]>

Run 'make indent' on 'flog/'

cc193dc

Separate commit for easier criu-dev <-> master transfer. Acked-by: Mike Rapoport <[email protected]> Signed-off-by: Adrian Reber <[email protected]>

flog: typo: mmaped -> mmapped

1fa21a0

It is mapped, not maped. Same applies for mmap I guess. Found by codespell, except it wants to change it to mapped, which will make it less specific. Signed-off-by: Kir Kolyshkin <[email protected]>

flog: fix some codespell warnings

7eaf7a3

Brought to you by codespell -w (using codespell v2.1.0). [v2: use "make indent" on the result] Signed-off-by: Kir Kolyshkin <[email protected]>

limit the field width of 'scanf'

aed3f34

Fixes: checkpoint-restore#2121 Signed-off-by: Pengda Yang <[email protected]>

sk-inet: Add IP TOS socket option

d6860d0

The TOS(type of service) field in the ip header allows you specify the priority of the socket data. Signed-off-by: Suraj Shirvankar <[email protected]>

zdtm: Add tests for ip tos restore

0dd4668

Signed-off-by: Suraj Shirvankar <[email protected]>

dump: increase fcntl call failure judgment

13eb876

The pipe_size type is unsigned int, when the fcntl call fails and return -1, it will cause a negative rollover problem. Signed-off-by: zhoujie <[email protected]>

ci: fix new codespell errors

1d4c5ed

Signed-off-by: Adrian Reber <[email protected]>

scripts: make newer versions of shellcheck happy

d98c533

Signed-off-by: Adrian Reber <[email protected]>

lib/c: add empty_ns interfaces to libcriu

f57bda4

crun wants to set empty_ns and this interface is missing from the library. This adds it to libcriu. Signed-off-by: Adrian Reber <[email protected]>

criu-ns: Add --criu-binary argument to run_criu()

f308272

--criu-binary argument provides a way to supply the CRIU binary location to run_criu(). Related to: checkpoint-restore#1909 Signed-off-by: Dhanuka Warusadura <[email protected]>

criu-ns: Add tests for criu-ns script

8094df8

These changes add test implementations for criu-ns script. Fixes: checkpoint-restore#1909 Signed-off-by: Dhanuka Warusadura <[email protected]>

criu-ns: Install Python pathlib module in CentOS 7

f0e9358

These changes fix the `ImportError: No module named pathlib` error when executing criu-ns tests located at criu/test/others/criu-ns Signed-off-by: Dhanuka Warusadura <[email protected]>

criu-ns: Update shebang line to python

9130fef

CentOS 7 CI environment uses Python 2. To execute criu-ns script in CentOS 7 changing the current shebang line to python is required. This reverse the changes made in a15a63f Signed-off-by: Dhanuka Warusadura <[email protected]>

action-scripts: Add pre-stream hook

104a828

This hook allows to start image streamer process from an action script. Signed-off-by: Radostin Stoyanov <[email protected]>

Fix mount(cgroup2) for older kernels.

11288c9

Linux 4.15 doesn't like empty string for cgroup2 mount options. Pass NULL then to satisfy the kernel check. Log the options for easier debugging. Signed-off-by: Michał Mirosław <[email protected]>

Log if prctl(SET_THP_DISABLE) doesn't work as expected.

7ca6856

If prctl(SET_THP_DISABLE) is not used due to bad semantics, log it for easier debugging. Signed-off-by: Michał Mirosław <[email protected]>

zdtm: thp_disable: Output a single failure message

d3a33ca

While at it, don't carry over stale errno to the fail() message. Signed-off-by: Michał Mirosław <[email protected]>

zdtm: thp_disable: Verify prctl(THP_DISABLE) migration

6006cb6

Signed-off-by: Michał Mirosław <[email protected]>

zdtm: thp_disable: Verify MADV_NOHUGEPAGE before migration

c75c017

Add a sanity check for THP_DISABLE. This discovered a broken commit in Google's kernel tree. Signed-off-by: Michał Mirosław <[email protected]>

simonis force-pushed the skip-zero-pages branch from 9bdc424 to 9fe9d22 Compare January 16, 2024 16:24

rst0git reviewed Jan 16, 2024

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rst0git added 3 commits January 16, 2024 22:27

test/nfconntrack: use nft or iptables-legacy

e5f4d8c

nft does not support xtables compat expressions https://git.netfilter.org/nftables/commit/?id=79195a8cc9e9d9cf2d17165bf07ac4cc9d55539f Signed-off-by: Radostin Stoyanov <[email protected]>

net: add error messages for restore of nftables

8f4430d

Show appropriate error messages when restore of nftables fails. Signed-off-by: Radostin Stoyanov <[email protected]>

simonis force-pushed the skip-zero-pages branch from 9fe9d22 to 4c04936 Compare January 18, 2024 15:37

rst0git reviewed Jan 19, 2024

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avagin reviewed Jan 21, 2024

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avagin added 3 commits January 20, 2024 23:46

kerndat: check the PAGEMAP_SCAN ioctl

615e45e

PAGEMAP_SCAN is a new ioctl that allows to get page attributes in a more effeciant way than reading pagemap files. Signed-off-by: Andrei Vagin <[email protected]>

page-cache: use the PAGEMAP_SCAN ioctl when it is available

bfa9428

Signed-off-by: Andrei Vagin <[email protected]>

pagemap-cache: add an ability to run tests without PAGEMAP_SCAN

50190ae

This change adds a new injectable fault (135) to disable PAGEMAP_SCAN and fault back to read pagemap files. Signed-off-by: Andrei Vagin <[email protected]>

simonis force-pushed the skip-zero-pages branch 2 times, most recently from 4bddca9 to 9d70e5f Compare January 24, 2024 15:59

simonis force-pushed the skip-zero-pages branch from 9d70e5f to b23ad22 Compare January 24, 2024 18:05

rst0git reviewed Jan 31, 2024

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github-actions bot added the stale-pr label Mar 8, 2024

avagin added no-auto-close Don't auto-close as a stale issue and removed stale-pr labels Mar 8, 2024

avagin force-pushed the criu-dev branch from 266f150 to f5dec05 Compare October 31, 2024 06:45

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Don't dump pages which only contain zero bytes #2331

Don't dump pages which only contain zero bytes #2331

simonis commented Jan 15, 2024

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rst0git commented Jan 19, 2024

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simonis commented Jan 22, 2024

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simonis commented Mar 8, 2024

Don't dump pages which only contain zero bytes #2331

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Don't dump pages which only contain zero bytes #2331

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simonis commented Jan 15, 2024

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avagin Jan 25, 2024 • edited Loading

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simonis commented Jan 22, 2024

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rppt commented Feb 3, 2024 via email

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simonis commented Mar 8, 2024

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