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Line 1: − + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + − + + + + + + + + − This is the replacement for (rather nasty) criu show code. Also this is the way to edit the images before restoring from them.+ + + + − === Convert to json (and back) ===+ + + + + + + + + + + + + + + + + + − Same as before, but the human-readable format is JSON+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + − All the needed information is in core-$pid.img and pagemap-$pid.img+ + + + + + + + + + + + + + + + + + + + + − + + + + + + + + + + + + + + + +
→Planned functionality
This page describes the CRiu Image Tool.
This page describes the CRiu Image Tool. CRIT is a feature-rich replacement for existing "criu show".
It is written completely in Python, so it is quite easy to read the code and extend its features.
== Usage ==
<pre>
usage: crit [-h] {decode,encode,info,x,show} ...
CRiu Image Tool
positional arguments:
{decode,encode,info,x,show}
Use crit CMD --help for command-specific help
decode convert criu image from binary type to json
encode convert criu image from json type to binary
info show info about image
x explore image dir
show convert criu image from binary to human-readable json
optional arguments:
-h, --help show this help message and exit
</pre>
=== Pretty output ===
Command <decode> prints JSON text in one line. This can be read by any further JSON-aware tool for parsing. For human eyes it's more convenient to read JSON multi-line with indentation. CRIT can do this when using the <code>show</code> action or the <code>--pretty</code> option.
Wend doing pretty optput CRIT does a little bit more, than just multiline indented JSON.
; Addresses and registers
: VM addresses and core.img register values are all printed in hex. Since JSON doesn't support this form of numbers, such fields are encoded as strings.
; Bit-fields
: Such things as flags and masks (e.g. sig-block mask) are also better understood when written in hex, so CRIT does this.
; IP addresses
: By default those a printed in decimal, but the "1.2.3.4" for v4 or "::1" for v6 can be seen in the --pretty mode.
; Symbolic names for flags
: Some known bit sets (e.g. MAP_PRIVATE, MAP_ANONYMOUS, etc. for vma->flags) are shown with names.
; Device numbers
: If the field is known to be of <code>dev_t</code> type, it's printed in the <code>major:minor</code> manner
== Functionality ==
== Functionality ==
=== Convert images to human-readable and back ===
=== Convert images to JSON and back ===
This is the replacement for (rather nasty) <code>criu show</code> code. Also this is the way to edit the images before restoring from them.
It uses [https://developers.google.com/protocol-buffers/docs/reference/python/google.protobuf.text_format-module text_format] as a human-readable format for protobuf messages.
The output file is structured in the following way.
Without "--pretty":
<pre>
{ "magic" : "FOO", "entries" : [{"foo": "bar", "bar": "foo", "extra": "abc"}, {"foo": "bar", "bar" : "foo", "extra" : "abc"} ]}
</pre>
With "--pretty":
<pre>
{
"magic" : "FOO",
"entries" : [
{
"foo" : "bar",
"bar" : "foo",
"extra" : "abc"
},
{
"foo" : "bar",
"bar" : "foo",
"extra" : "abc"
}
]
}
</pre>
<div class="toccolours mw-collapsible mw-collapsed" style="width:800px">
<b>Example("crit decode -i core-5679.img --pretty")</b>
<div class="mw-collapsible-content">
<pre>
{
"magic": "CORE",
"entries": [
{
"mtype": "X86_64",
"thread_core": {
"futex_rla_len": 24,
"sched_policy": 0,
"sched_nice": 0,
"futex_rla": 0,
"signals_p": {},
"sas": {
"ss_size": 0,
"ss_sp": 0,
"ss_flags": 2
}
},
"thread_info": {
"fpregs": {
"st_space": [
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0
],
"fop": 0,
"rdp": 0,
"twd": 0,
"mxcsr": 8064,
"swd": 0,
"rip": 0,
"xsave": {
"ymmh_space": [
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0
],
"xstate_bv": 2
},
"xmm_space": [
0,
4278190080,
4294967295,
4294967295,
1701145715,
3219568,
0,
0,
0,
0,
33,
0,
792358505,
1953460082,
1852400175,
0,
942882145,
876295483,
774519349,
1031303283,
893073459,
976565307,
1937255978,
859661936,
993344312,
3814708,
65,
0,
37049520,
0,
37049632,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
4294901760,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0
],
"cwd": 0,
"mxcsr_mask": 65535
},
"clear_tid_addr": 0,
"gpregs": {
"gs": "0x0",
"ip": "0x7f172cf1ea04",
"cx": "0xffffffffffffffff",
"cs": "0x33",
"ax": "0x38",
"orig_ax": "0x38",
"di": "0x1200011",
"es": "0x0",
"gs_base": "0x0",
"r14": "0x0",
"r15": "0x2355e00",
"r12": "0x7ffffdbf74f0",
"r13": "0x0",
"r10": "0x7f172d83d9d0",
"r11": "0x246",
"fs_base": "0x7f172d83d700",
"bp": "0x7ffffdbf7530",
"dx": "0x0",
"bx": "0x0",
"ds": "0x0",
"ss": "0x2b",
"sp": "0x7ffffdbf74f0",
"r8": "0x0",
"r9": "0x0",
"fs": "0x0",
"si": "0x0",
"flags": "0x246"
}
},
"tc": {
"timers": {
"real": {
"isec": 0,
"vusec": 0,
"iusec": 0,
"vsec": 0
},
"virt": {
"isec": 0,
"vusec": 0,
"iusec": 0,
"vsec": 0
},
"prof": {
"isec": 0,
"vusec": 0,
"iusec": 0,
"vsec": 0
}
},
"cg_set": 1,
"signals_s": {},
"blk_sigset": "0x10002",
"exit_code": 0,
"rlimits": {
"rlimits": [
{
"max": 18446744073709551615,
"cur": 18446744073709551615
},
{
"max": 18446744073709551615,
"cur": 18446744073709551615
},
{
"max": 18446744073709551615,
"cur": 18446744073709551615
},
{
"max": 18446744073709551615,
"cur": 8388608
},
{
"max": 18446744073709551615,
"cur": 0
},
{
"max": 18446744073709551615,
"cur": 18446744073709551615
},
{
"max": 62844,
"cur": 62844
},
{
"max": 4096,
"cur": 1024
},
{
"max": 65536,
"cur": 65536
},
{
"max": 18446744073709551615,
"cur": 18446744073709551615
},
{
"max": 18446744073709551615,
"cur": 18446744073709551615
},
{
"max": 62844,
"cur": 62844
},
{
"max": 819200,
"cur": 819200
},
{
"max": 0,
"cur": 0
},
{
"max": 0,
"cur": 0
},
{
"max": 18446744073709551615,
"cur": 18446744073709551615
}
]
},
"comm": "loop.sh",
"flags": 1077960704,
"task_state": 1,
"personality": 0
}
}
]
}
</pre>
</div>
</div>
=== Generate core files out of task images ===
=== Generate core files out of task images ===
Moved into separate project called [[criu-coredump]].
=== Show images statistics ===
E.g. -- total number of processes, files, memory, sockets, etc.
Use
<pre>
crit x $directory_with_images <explore type>
</pre>
Supported explorers are
;'ps'
:to show process tree
;'fds'
:to show files used by tasks
;'mems'
:to show memory mappings info
== Planned functionality ==
=== On-the-fly conversion ===
=== On-the-fly conversion ===
There's an idea to make CRIU spawn CRIT and read images "through" it, to allow for at-the-restore-time modifications
There's an idea to make CRIU spawn CRIT and read images "through" it, to allow for at-the-restore-time modifications. For details, see https://github.com/xemul/criu/issues/59.
=== Convert between different image versions ===
=== Convert between different image versions ===
Right now we store the images version in inventory.img and collect info about [[what's bad with V1 images]]. If some day we have v2, CRIT will convert from v1. And for backward compatibility we'll use on-the-fly conversion when restoring from old images.
Right now we store the images version in inventory.img and collect info about [[what's bad with V1 images]]. If some day we have v2, CRIT will convert from v1. And for backward compatibility we'll use on-the-fly conversion when restoring from old images.
=== Check/validate images ===
Check that
* all images are present
* the inter-images IDs are in consistent state
For details, see https://github.com/xemul/criu/issues/44.
=== [[Anonymize image files]] ===
Since images contain raw memory dumps people may refuse to send us images for debugging. Need to anonymize them, i.e. -- remove this sensitive information.
[[Category:Images]]
[[Category:API]]