DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
Receipt is acknowledged of a request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e) and a submission, filed on November 23rd, 2025.
Response to Amendment
The amendment filed on November 23rd, 2025 has been entered.
The amendment of claims have been acknowledged. Claim 4 is canceled. Claims 1-3 and 5-20 are currently pending.
In view of the amendments, objections to claims 7 and 14, and rejection of claim 12 under 35 USC 112(b) are withdrawn.
Response to Arguments
Applicant's arguments with respect to the independent claims 1, 10 and 16 filed November 23rd, 2025 have been fully considered but they are not persuasive.
Regarding the rejection of claims, Applicant argued:
In the Response to Arguments, the Examiner found that the claims "do not explicitly recite any limitations that may be interpreted as defining the first garbage collection rate and the second garbage collection rate as mutually exclusive." (FOA, pg. 5) To address this concern, Applicant submits the proposed amended claims recite two separate determinations that are performed, determining a garbage collection rate when there is a first I/O access pattern and then determining a garbage collection rate when there is a second I/O access pattern, wherein the first I/O access pattern is higher than the second I/O access pattern. Thus, the claims explicitly recite two mutually exclusive garbage collection rates, which trigger different garbage collection operations, based on whether there is a first I/O access pattern or a second I/O access pattern. The claims require operations under both the first and second garbage collection rates. The garbage collection rates are mutually exclusive because the first I/O access pattern is higher than the second I/O access pattern. Thus, the two different garbage collection rates and different garbage collection operations occur under different circumstances depending on whether the first I/O access pattern or the second I/O access pattern is occurring.
Further, the amended claims recite different garbage collection operations for the first garbage collection rate and the second garbage collection rate. The first garbage collection is performed while the available free space is below a first threshold and the second garbage collection is performed when the available free space is below a second threshold and when the blocks have more than a threshold number of invalid pages. Thus, the claims perform two different types of garbage collections that involve different operations and determinations.
The Examiner cited paras. 20-22 of Chen as teaching that the first and the second garbage collection rates are performed for a first I/O access pattern and second I/O access pattern respectively, such that the first pattern is lower than the second I/O access pattern. (FOA, pg. 12)
The cited para. 20 of Chen mentions an AI module may generate a determination result based on occurrence of read commands and wrote commands from the host. Para. 21 mentions determining a user's tendency for read or write operations to determine garbage collection strategy. If the determination indicates user tendency for read ops, then a first control strategy may do a read scan operation with the higher frequency to more actively read the data pages of blocks. If the behavior has fewer writes, then the first control strategy may have less aggressive garbage collection. If the behavior has more writes, the second control strategy used by the microprocessor may include more aggressive garbage collection. Para. 22 mentions if the determination indicates the user's tendency is write operations, then the second control strategy used may include read scan operations with lower frequency. For more write operations, the second control strategy may have more aggressive garbage collection operations.
The cited Chen discusses more aggressive garbage collection if the user behavior has more writes and if the user behavior has more reads, then do read scan operations at higher frequency. This does not teach the claimed different operations depending on whether there is the first I/O access pattern or second I/O access pattern, where the first I/O access pattern is higher than the second. For instance, in the claims if there is the higher first I/O access pattern, then garbage collection is initiated when free space is below a first threshold. This is nowhere taught in the cited Chen or other cited art. Further, if there is the second, lower, I/O access pattern, then there is garbage collection in response to one of two conditions, available free space is below a second threshold or when blocks have more than a threshold number of invalid pages. The cited Chen does not teach these different garbage collection operations depending on the I/O access pattern. Instead, Chen mentions more aggressive garbage collection if more write ops, then reads, or if there are more read ops, then do more read scan operations.
Although the cited Chen discusses two different garbage collection strategies (para. 22) and Bhardwaj (para. 44) discusses initiating garbage collection in response to a shortage of blocks, the amended independent claims require determining first and second garbage collection rates when there is a first I/O access pattern and second I/O access pattern, respectively, such that the first I/O access pattern is higher than the second I/O access pattern. The first garbage collection for the first garbage collection rate is initiated if available free space is below a first threshold. The second garbage collection for the second garbage collection rate is initiated under one of two different conditions occurring when the available free space is below a second threshold or when the blocks have more than a threshold number of invalid pages.
The Examiner cited paras. 44, 45, and 58 of Bhardwaj as teaching the pre-amended limitation for the second garbage collection rate. (FOA, pg. 10) Applicant traverses with respect to the amended limitation reciting:
determining a second garbage collection rate when there is a second I/O access
pattern at the storage device, wherein the first I/O access pattern is higher than the second
I/O access pattern; and
in response to determining the second garbage collection rate, initiating a second garbage collection when the available free space is below a second threshold or when the blocks have more than a threshold number of invalid pages.
The cited para. 44 of Bhardwaj mentions the garbage collection (GC) operation is performed due to a shortage of free blocks. The cited para. 45 mentions determining physical blocks corresponding to logical blocks and has a heat map indicating update frequency or hotness of a region. When garbage collection is triggered, the system can select a block for garbage collection using the heat map. The system can select a source block from a region based on amount of valid data below a threshold. Para. 58 mentions once a region is selected based on data access, heat map selects a block from selected region based on amount of valid data. Blocks having a least amount of valid data is determined.
Although the cited Bhardwaj discusses how to select blocks to garbage collect, there is no teaching of the claimed determinations of a first and second garbage collection rates when there is a first I/O access pattern and second I/O access pattern, respectively, and then performing a first garbage collection and second garbage collection under different conditions being satisfied.
The cited Bhardwaj mentions one determination for garbage collection, not different determinations of operating under a first garbage collection rate and then a second garbage collection rate based on the I/O access pattern, and then within the first garbage collection rate and the second garbage collection rate, performing garbage collection upon different conditions being satisfied. The different conditions for the first and second garbage collection rate include initiating a first garbage collection when the available free space is below a first threshold for the first garbage collection rate or initiating a second garbage collection when the available free space is below a second threshold or when the blocks have more than a threshold number of invalid pages for the second garbage collection rate.
Accordingly, amended claims 1, 10, and 16 are patentable over the cited art because the cited combination does not teach or suggest all the claim requirements.
Examiner respectfully disagrees.
In particular, while Applicant asserts now the claims are amended to “explicitly recite two mutually exclusive garbage collection rates, which trigger different garbage collection operations, based on whether there is a first I/O access pattern or a second I/O access pattern”, the claim limitations are not clearly reflective of the extent or scope of the “mutual exclusiveness”.
As stated in the previous Office Action’s “response to arguments” section:
As for the 2 determination steps recited the claim limitations, the cited references CHEN and BHARDWAJ both discloses continuous monitoring /determination of garbage collection conditions, where “determination” of such conditions are done repeatedly during device operations. This may be reasonably interpreted as multiple individual “determination” steps.
That is, while Applicant’s claims recite 2 determination steps, there is no explicit recitation (nor is there support for) 2 determined conditions (the 2 garbage collection rates, and/or the 2 I/O access patterns) to be met at the same time, or at different times.
Therefore, at least as admitted by Applicant’s own statements, CHEN discloses the 2 determinations steps with 2 determined conditions (the 2 garbage collection rates, the 2 I/O access patterns). “Para. 21 mentions determining a user's tendency for read or write operations to determine garbage collection strategy. If the determination indicates user tendency for read ops, then a first control strategy may do a read scan operation with the higher frequency to more actively read the data pages of blocks. If the behavior has fewer writes, then the first control strategy may have less aggressive garbage collection. If the behavior has more writes, the second control strategy used by the microprocessor may include more aggressive garbage collection.” – stated by Applicant above.
Applicant further argued that CHEN “does not teach the claimed different operations depending on whether there is the first I/O access pattern or second I/O access pattern, where the first I/O access pattern is higher than the second”, and BHARDWAJ does not teach “the claimed determinations of a first and second garbage collection rates when there is a first I/O access pattern and second I/O access pattern, respectively, and then performing a first garbage collection and second garbage collection under different conditions being satisfied”.
However, Examiner notes that while the claims recite a first garbage collection and second garbage collection under different conditions, the 2 “garbage collections” themselves are not defined by the claims as mutually exclusive operations without any overlaps. (not exclusively for some blocks, or some pages, or by some unique operations/strategies, etc.) Indeed it is evident from claim 3 at least, that “first garbage collection and the second garbage collection” operate similarly, “wherein the first garbage collection and the second garbage collection processes the blocks from a highest number to a lowest number of invalid pages”. ONLY the conditions or triggers for the 2 garbage collections are different in the claims. First and second “garbage collection rates” are merely recited as conditions, and do not define any differences in the first and second “garbage collection” operations.
Thus, Applicant’s argument regarding “claimed different operations” is moot, because the claims do not recite or define any differences or exclusivity between “first garbage collection” and “second garbage collection” other than their respective triggers and conditions.
Even if Applicant’s interpretation is that “first garbage collection” and “second garbage collection” are different solely because of their respective triggers and conditions, then CHEN teaches claimed determined first I/O access pattern and second I/O access pattern, and BHARDWAJ teaches performing (first and second) garbage collections under multiple different sets of conditions, as recited by the claims.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
Claims 1-3 and 5-20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Amended independent claims 1, 10 and 15 each recite in part, “wherein the first I/O access pattern is higher than the second I/O access pattern”.
This claim limitation is not supported by the specification originally filed by the Applicant.
While the Applicant indicated this claim limitation is based on claim limitation in previous claim 4, the new claim limitation language is significantly different from those of previous claim 4, which recited in part “wherein the first garbage collection rate corresponds to the I/O access pattern indicating a first I/O access rate at the storage device and wherein the second garbage collection rate corresponds to the I/O access pattern indicating a second I/O access rate at the storage device, wherein the first I/O access rate is lower than the second I/O access rate”.
Applicant’s new claim limitation above appears to be based somewhat on [0018] of the specification which recites “Described embodiments determine a garbage collection rate based on the I/O access patterns, such that a relatively high I/O access pattern results in a minimum garbage collection rate to garbage collect at a lower rate than garbage collection for lower I/O access patterns. In this way, more resources are directed to garbage collection for relatively lower I/O access rates when garbage collection will not have much effect on I/O access latency, and fewer resources are directed to garbage collection for relatively higher I/O access rates so as not to increase I/O latency”, and also on [0024] with similar language “A higher I/O access pattern corresponds to a lower garbage collection rate and a relatively lower I/O access pattern corresponds to a higher garbage collection rate because increasing garbage collection for low I/O access rates should not affect storage performance.”
Examiner notes that the key difference and issue here is one of grammar: Applicant’s specification recited “high I/O access pattern” and “lower I/O access patterns”, where “high” and “lower” are adjectives for “I/O access” which implies I/O access rates, and NOT adjectives for “pattern(s)”. “Pattern(s)” cannot be said to be “high” or “low”. Thus, it is grammatically incorrect and confusing to recite “wherein the first I/O access pattern is higher than the second I/O access pattern”. In any case, this claim limitation language is significantly different enough from the previous claim 4 and the specification, in such a way as to not reasonably convey to one skilled in the relevant art that the inventor(s), at the time the application was filed, had possession of the claimed invention.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
Claims 1-3 and 5-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Where applicant acts as his or her own lexicographer to specifically define a term of a claim contrary to its ordinary meaning, the written description must clearly redefine the claim term and set forth the uncommon definition so as to put one reasonably skilled in the art on notice that the applicant intended to so redefine that claim term. Process Control Corp. v. HydReclaim Corp., 190 F.3d 1350, 1357, 52 USPQ2d 1029, 1033 (Fed. Cir. 1999).
Amended independent claims 1, 10 and 15 each recite in part, “wherein the first I/O access pattern is higher than the second I/O access pattern”.
Examiner notes that the key difference and issue here is one of grammar: Applicant’s specification recited “high I/O access pattern” and “lower I/O access patterns”, where “high” and “lower” are adjectives for “I/O access” which implies I/O access rates, and NOT adjectives for “pattern(s)”. “Pattern(s)” cannot be said to be “high” or “low”. Thus, it is grammatically incorrect and confusing to recite “wherein the first I/O access pattern is higher than the second I/O access pattern”.
Because the usage of these terms by the Applicant are not clearly explainable by any special definitions in Applicant’s specification, nor do they fit the ordinary meaning as understood by one of ordinary skill in the art, the claim limitations are unclear and indefinite.
For the purpose of examination, the above recited claim limitation shall be interpreted as the claim limitation of previous claim 4 (which appears to be the intended claim limitation scope), “wherein the first garbage collection rate corresponds to the I/O access pattern indicating a first I/O access rate at the storage device and wherein the second garbage collection rate corresponds to the I/O access pattern indicating a second I/O access rate at the storage device, wherein the first I/O access rate is lower than the second I/O access rate”.
Claims 2-3, 5-9, 11-14, and 16-20 are rejected as dependent upon rejected independent claims 1, 10, and 15 above.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1, 2, 4-6, 8-11, 13, 15-18, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Chen et al., US Patent Application Publication Number 20200073571 (herein “CHEN”) in view of Bhardwaj, US Patent Application Publication Number 20220035735 (herein “BHARDWAJ”).
Regarding claim 1, CHEN discloses a storage device having a plurality of dies of blocks of pages of data to store data written from a host system (FIGs 1 and 2, flash memory module 130 with multiple blocks and pages to store data from host device 110 and controller 120),
wherein the storage device includes logic to perform operations (FIGs. 1, flash memory controller 120, or portions of it, may be considered as part of storage device with logic to perform operations), the operations comprising:
determining a first garbage collection rate when there is a first Input/Output (I/O) access pattern at the storage device; in response to determining the first garbage collection rate, initiating a first garbage collection; determining a second garbage collection rate when there is a second I/O access pattern at the storage device; and in response to determining the second garbage collection rate, initiating a second garbage collection (FIG. 3, [0020], “the AI module 122 may generate the determination result based on at least two of the following parameters: occurrence frequency of the read commands and the occurrence frequency of the write commands from the host device 110...”, [0021], “if the determination result indicates that the electronic device 100 has the first user behavior model…. first control strategy used by the microprocessor 124 may include less aggressive garbage collection operations (e.g. the garbage operation is triggered by a longer time or more invalid pages)”, [0022], “If the determination result indicates that the electronic device 100 has the second user behavior model…. the second control strategy used by the microprocessor 124 may include more aggressive garbage collection operations (e.g. the garbage operation is triggered by a shorter time or less invalid pages)”);
wherein the first I/O access pattern is higher than the second I/O access pattern (CHEN discloses 2 different garbage collection modes based on 2 different I/O access patterns, 1 being more aggressive than the other, see CHEN FIG. 3, [0020]-[0022]).
Chen does not explicitly disclose determining available free space; initiating a first garbage collection when the available free space below a first threshold; and initiating a second garbage collection when the available free space is below a second threshold or when the blocks have more than a threshold number of invalid pages.
BHARDWAJ discloses determining available free space; initiating a first garbage collection in response to the available free space below a first threshold (FIG. 2, [0044], “The memory sub-system can further determine whether the GC operation should be performed due to shortage of free blocks, as depicted in decision point 220.”); and
initiating a second garbage collection when the available free space is below a second threshold or when the blocks have more than a threshold number of invalid pages (FIG. 2, [0044], “The memory sub-system can further determine whether the GC operation should be performed due to shortage of free blocks, as depicted in decision point 220.” [0045], “The memory sub-system 200 can then select a source block from the set of blocks associated with the selected region based on the amount of valid data, such as a block with an amount of valid data below a threshold amount of valid data”. [0058], “the heat map component 113 can then select a particular block from the set of blocks associated with the selected region, based on the amount of valid data. For example, the block with the least amount of valid data (e.g. more than some threshold amount of invalid data in pages) can be selected as the source block for the GC operation…. physical block PB9 can contain only one page PG12 that has valid data and the remaining pages with invalid data.” E.g. Garbage collection is done when free space is below some threshold and on blocks with more than some threshold of invalid pages. BHARDWAJ’s criterion for garbage collection can be combination of multiple different metrics.)
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify CHEN’s garbage collection in NVM to further include BHARDWAJ’s garbage collection based on free space and invalid pages, to increase the endurance and operating lifespan of the memory sub-system, reduce write operations in the garbage collection operations (see BHARDWAJ [0022]).
Regarding claim 2, CHEN does not explicitly disclose the storage device of claim 1, wherein for the second garbage collection rate, the second garbage collection is initiated for determined blocks having more than the threshold number of invalid pages in response to the available free space exceeding the second threshold.
BHARDWAJ discloses the storage device of claim 1, wherein for the second garbage collection rate, the second garbage collection is initiated for determined blocks having more than the threshold number of invalid pages in response to the available free space exceeding the second threshold (FIG. 2, [0044], “The memory sub-system can further determine whether the GC operation should be performed due to shortage of free blocks, as depicted in decision point 220.” [0045], “The memory sub-system 200 can then select a source block from the set of blocks associated with the selected region based on the amount of valid data, such as a block with an amount of valid data below a threshold amount of valid data”. [0058], “the heat map component 113 can then select a particular block from the set of blocks associated with the selected region, based on the amount of valid data. For example, the block with the least amount of valid data (e.g. more than some threshold amount of invalid data in pages) can be selected as the source block for the GC operation…. physical block PB9 can contain only one page PG12 that has valid data and the remaining pages with invalid data.” E.g. Garbage collection is done when free space is below some threshold and then selected on blocks with more than some threshold of invalid pages).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify CHEN’s garbage collection in NVM to further include BHARDWAJ’s garbage collection based on free space and invalid pages, to increase the endurance and operating lifespan of the memory sub-system, reduce write operations in the garbage collection operations (see BHARDWAJ [0022]).
Regarding claim 5, CHEN discloses the storage device of claim 1, continually performing the first garbage collection and the second garbage collection according to the first garbage collection rate and the second garbage collection rate, respectively, until a change to the first garbage collection rate or the second garbage collection rate (FIG. 3, [0020], “the AI module 122 may generate the determination result based on at least two of the following parameters: occurrence frequency of the read commands and the occurrence frequency of the write commands from the host device 110...”, [0021], “if the determination result indicates that the electronic device 100 has the first user behavior model…. first control strategy used by the microprocessor 124 may include less aggressive garbage collection operations (e.g. the garbage operation is triggered by a longer time or more invalid pages)”, [0022], “If the determination result indicates that the electronic device 100 has the second user behavior model…. the second control strategy used by the microprocessor 124 may include more aggressive garbage collection operations (e.g. the garbage operation is triggered by a shorter time or less invalid pages)” e.g. GC can continue in 1 of the 2 modes/rates until the mode/rate is changed to the other of the 2 modes/rates).
Regarding claim 6, CHEN discloses the storage device of claim 1, wherein there is a third garbage collection rate based on the I/O access pattern at the storage device ([0023], “In the above embodiments, only two user behavior models and only two control strategies are provided, however, these are not a limitation of the present invention. In other embodiments, the memory controller 120 may have other user behavior models such as the count/frequency of sudden power off recovery (SPOR), or average idle time of the memory controller 120 and memory module 130, and the microprocessor 124 can generate the corresponding control strategy to optimize the efficiency and life of the memory module 130.” E.g. additional /third garbage collection rates based on I/O access pattern).
CHEN does not explicitly disclose wherein a full reclamation garbage collection is performed.
BHARDWAJ discloses wherein a full reclamation garbage collection is performed (full reclamation garbage collection may be interpreted as continuous GC until some threshold of free space or some threshold of invalid space is met, see Applicant’s written description [0038]. BHARDWAJ discloses FIG. 2, [0044], “The memory sub-system can further determine whether the GC operation should be performed due to shortage of free blocks, as depicted in decision point 220.”).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify CHEN’s garbage collection in NVM to further include BHARDWAJ’s garbage collection based on free space and invalid pages, to increase the endurance and operating lifespan of the memory sub-system, reduce write operations in the garbage collection operations (see BHARDWAJ [0022]).
Regarding claim 8, CHEN discloses the storage device of claim 1, wherein the determining one of the first garbage collection rate and the second garbage collection rate comprises: receiving, from the host system, indication of one of the first garbage collection rate and the second garbage collection rate determined at the host system (FIG. 1, the AI module 122 which performs the mode determination in CHEN may be considered a part of the host system).
Regarding claim 9, CHEN discloses the storage device of claim 1, further comprising: a predictive model to monitor I/O access patterns at the storage device to determine one of the first garbage collection rate and the second garbage collection rate based on the monitored I/O access patterns (FIG. 1, [0013], “AI module 122 employs a Deep Learning algorithm. In one embodiment, the AI module 122 utilizes an artificial neural network (ANN) architecture to predict the next read command based on the current read command.” E.g. the AI module 122 used to determine the GC modes/rates monitors I/O access patterns to predict future I/O patterns and GC modes); and
a garbage collection manager to manage garbage collection operations depending on the first garbage collection rate and the second garbage collection rate (FIG. 1, control logic 129 performing controls of the memory including GC operations).
Regarding claim 10, the applicant is directed to the rejections to claim 1 set forth above, as they are rejected based on the same rationale.
Regarding claim 11, the applicant is directed to the rejections to claim 2 set forth above, as they are rejected based on the same rationale.
Regarding claim 13, the applicant is directed to the rejections to claim 6 set forth above, as they are rejected based on the same rationale.
Regarding claim 15, the applicant is directed to the rejections to claim 9 set forth above, as they are rejected based on the same rationale.
Regarding claim 16, the applicant is directed to the rejections to claim 1 set forth above, as they are rejected based on the same rationale.
Regarding claim 17, the applicant is directed to the rejections to claim 2 set forth above, as they are rejected based on the same rationale.
Regarding claim 18, the applicant is directed to the rejections to claim 6 set forth above, as they are rejected based on the same rationale.
Regarding claim 20, the applicant is directed to the rejections to claim 9 set forth above, as they are rejected based on the same rationale.
Claims 3 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over CHEN in view of BHARDWAJ, further in view of Saxena et al., US Patent Application Publication Number 20200097403 (herein “SAXENA”)
Regarding claim 3, CHEN and BHARDWAJ do not explicitly disclose the storage device of claim 1, wherein the operations further comprise: ordering the blocks by number of invalid pages, wherein the first garbage collection and the second garbage collection processes the blocks from a highest number to a lowest number of invalid pages.
SAXENA discloses the storage device of claim 1, wherein the operations further comprise: ordering the blocks by number of invalid pages, wherein the first garbage collection and the second garbage collection processes the blocks from a highest number to a lowest number of invalid pages (FIG. 2, [0025]-[0026], “In particular, the block selection process of blocks 204, 206, 208, and 210 includes determining or selecting a best source or victim block from which to copy remaining valid data based on valid pages in the closed block…. This search is an iterative process in which a data storage device controller (e.g., controller 108 in FIG. 1), for example, and more particularly a garbage collector circuit (e.g., circuit 118) sequentially examines each of the closed blocks in the closed block pool by determining whether a minimum valid page count (MinValidPageCount or MinVPC) is less than a current MinVPC as illustrated by decision block 208.” E.g. continuously performing garbage collection on blocks ranked by highest to lowest number of invalid pages, or lowest to highest number of valid pages).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify CHEN’s garbage collection in NVM with BHARDWAJ’s garbage collection based on free space and invalid pages, to further include SAXENA’s garbage collection ranking blocks based on number of invalid pages, to select best source/victim blocks for garbage collection (see SAXENA [0003]).
Regarding claim 12, the applicant is directed to the rejections to claim 3 set forth above, as they are rejected based on the same rationale.
Allowable Subject Matter
Claims 7, 14, and 19 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims and corrected for informalities.
The following is a statement of reasons for the indication of allowable subject matter:
None of the cited references discloses or suggests the following underlined features:
7. The storage device of claim 6, wherein the full reclamation garbage collection comprises:
performing a third garbage collection for blocks having a number of invalid pages greater than a threshold number of invalid pages;
in response to no blocks having a number of invalid pages greater than the threshold number of invalid pages, determining a percentage comprising a number of invalid pages in blocks having less than the threshold number of invalid pages divided by total space; and
in response to the percentage greater than a threshold percentage, performing a fourth garbage collection on the blocks with a highest number of invalid pages less than the threshold number of invalid pages.
14. The storage controller of claim 13, wherein the full reclamation garbage collection comprises:
performing a third garbage collection for blocks having a number of invalid pages greater than a threshold number of invalid pages;
in response to no blocks having a number of invalid pages greater than the threshold number of invalid pages, determining a percentage comprising a number of invalid pages in blocks having less than the threshold number of invalid pages divided by total space; and
in response to the percentage greater than a threshold percentage, performing a fourth garbage collection on the blocks with a highest number of invalid pages less than the threshold number of invalid pages.
19. The method of claim 18, wherein the full reclamation garbage collection comprises:
performing a third garbage collection for blocks having a number of invalid pages greater than a threshold number of invalid pages;
in response to no blocks having a number of invalid pages greater than the threshold number of invalid pages, determining a percentage comprising a number of invalid pages in blocks having less than the threshold number of invalid pages divided by total space; and
in response to the percentage greater than a threshold percentage, performing a fourth garbage collection on the blocks with a highest number of invalid pages less than the threshold number of invalid pages.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHEN GU whose telephone number is (571) 270-1208. The examiner can normally be reached M-F 10:30am-8:00pm ET.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jared Rutz can be reached on (571) 272-5535. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
CHEN GU
Examiner
Art Unit 2135
/C.G./Examiner, Art Unit 2135
/JARED I RUTZ/Supervisory Patent Examiner, Art Unit 2135