rafs: minor optimization for tarfs builder

[jiangliu]

Minor optimization for tarfs builder.

[anolis-bot]

@jiangliu , a new test job has been submitted. Please wait in patience. The test job url: https://tone.openanolis.cn/ws/nrh4nnio/test_result/69013

[anolis-bot]

@jiangliu , the code has been updated, so a new test job has been submitted. Please wait in patience. The test job url: https://tone.openanolis.cn/ws/nrh4nnio/test_result/69016

[anolis-bot]

@jiangliu , The CI test is completed, please check result:

Test Case		Test Result
build rust golang image		✅ SUCCESS
compile nydusd		✅ SUCCESS
compile ctr remote		✅ SUCCESS
compile nydus snapshotter		✅ SUCCESS
run container with rafs		✅ SUCCESS
run container with zran		✅ SUCCESS
run container with rafs and compile linux		✅ SUCCESS

Congratulations, your test job passed!

[anolis-bot]

@jiangliu , the code has been updated, so a new test job has been submitted. Please wait in patience. The test job url: https://tone.openanolis.cn/ws/nrh4nnio/test_result/69027

[codecov]

Codecov Report

Merging #1233 (7d41a79) into master (79f4a68) will not change coverage.
The diff coverage is 40.00%.

@@           Coverage Diff           @@
##           master    #1233   +/-   ##
=======================================
  Coverage   41.35%   41.35%           
=======================================
  Files         126      126           
  Lines       37332    37332           
  Branches    37332    37332           
=======================================
  Hits        15440    15440           
- Misses      21159    21160    +1     
+ Partials      733      732    -1     

Impacted Files	Coverage Δ
rafs/src/builder/core/tree.rs	40.00% <0.00%> (ø)
rafs/src/builder/core/node.rs	26.45% <66.66%> (ø)

... and 3 files with indirect coverage changes

[github-actions]

benchmark-result	pull-elapsed(s)	create-elapsed(s)	run-elapsed(s)	total-elapsed(s)
nydus-all-prefetch	0.682590	2.551828	21.926234	25.160652
nydus-filelist-prefetch	0.684412	2.012418	8.067677	10.764507
nydus-no-prefetch	0.696426	0.802546	9.753070	11.252042
oci	29.497472	0.303956	1.334975	31.136403
zran-all-prefetch	1.101368	3.331692	22.407013	26.840073

[anolis-bot]

@jiangliu , The CI test is completed, please check result:

Test Case		Test Result
build rust golang image		✅ SUCCESS
compile nydusd		✅ SUCCESS
compile ctr remote		✅ SUCCESS
compile nydus snapshotter		✅ SUCCESS
run container with rafs		✅ SUCCESS
run container with zran		✅ SUCCESS
run container with rafs and compile linux		✅ SUCCESS

Congratulations, your test job passed!

[anolis-bot]

@jiangliu , The CI test is completed, please check result:

Test Case		Test Result
build rust golang image		✅ SUCCESS
compile nydusd		✅ SUCCESS
compile ctr remote		✅ SUCCESS
compile nydus snapshotter		✅ SUCCESS
run container with rafs		✅ SUCCESS
run container with zran		✅ SUCCESS
run container with rafs and compile linux		✅ SUCCESS

Congratulations, your test job passed!