 data, extract a time-to-data value from the table, reference the adder, and add the adder to the time-to-data value.
The access module may comprise a seeking module disposed within the control unit. In one embodiment, the seeking module is configured to receive a physical address of target data, receive the OTRC of the head involved in accessing the target data, and apply the OTRC to pick the optimal seek and/or tracking parameters for that OTRC. The seek is then performed to access the data at the target location.
An attendant method for employing customized off-track read capability (OTRC) in accessing data on a direct access storage device (DASD) comprises providing a DASD having a rotating data storage medium and a read head positionable for interaction with the data storage medium, determining the OTRC particular to the read head, and applying the OTRC in accessing data from the data storage medium.
Applying knowledge of the OTRC in accessing data from the DASD may comprise applying the OTRC dynamically during a seek operation and may also comprise applying the OTRC dynamically during a tracking operation. In one embodiment, determining the OTRC comprises measuring the OTRC of the read head during manufacturing of the DASD.
The method may further comprise providing a servo control loop within the DASD, and applying the OTRC in accessing data from the data storage medium may comprise applying the OTRC within the servo control loop. Preferably, the OTRC is applied to determine an optimal servo loop for seeking and/or tracking.
In one embodiment, applying the OTRC comprises applying the OTRC to a data seek algorithm to determine an optimal trajectory of the head to the target data. In yet another embodiment, applying the OTRC comprises applying the OTRC to a seek queuing algorithm to determine the order of seeking a plurality of blocks of target data by improving the read time estimates.
Applying the OTRC may also comprise referencing a table of time-to-data for various numbers of tracks traversed, the table incorporating the OTRC specific to the head. Additionally, applying the OTRC may comprise referencing a standard table of time-to-data values for various numbers of tracks traversed and applying an adder corresponding to the OTRC. Applying the OTRC may also comprise referencing from among a plurality of tables of time-to-data for
data, extract a time - to - data value from the mesa, reference the adder, and lend the adder to the time - to - data value. 
 The access faculty may comprise a seeking module qualify within the control unit. In one shape, the try module is configure to receive a physical address of target datum, receive the OTRC of the head imply in accessing the target datum, and apply the OTRC to pick the optimal seek and/or track parameters for that OTRC. The seek is then performed to access the datum at the target localization. 
 An attendant method for hire customized off - track read capability (OTRC) in accessing datum on a direct access storage device (DASD) comprises providing a DASD having a rotate datum storage medium and a read head positionable for interaction with the data storage medium, determining the OTRC especial to the read point, and applying the OTRC in accessing datum from the datum storage medium. 
 Applying knowledge of the OTRC in access data from the DASD may comprise applying the OTRC dynamically during a seek operation and may besides comprise applying the OTRC dynamically during a tracking operation. In one embodiment, determining the OTRC comprises measuring the OTRC of the read head during manufacturing of the DASD. 
 The method may further constitute providing a servo control condition loop within the DASD, and applying the OTRC in accessing data from the data repositing medium may comprise applying the OTRC within the servo control loop topology. Preferably, the OTRC is applied to determine an optimal servo loop for seek and/or tracking. 
 In one shape, applying the OTRC comprises applying the OTRC to a data seek algorithm to determine an optimum trajectory of the head to the target data. In yet another embodiment, enforce the OTRC comprises applying the OTRC to a seek queuing algorithm to determine the order of seeking a battalion of blocks of target data by better the read time estimates. 
 Applying the OTRC may also comprise reference a table of time - to - datum for various numbers of tracks cross, the table incorporating the OTRC specific to the head. Additionally, applying the OTRC may comprise referencing a standard table of time - to - data value for diverse number of tracks traversed and apply an adder corresponding to the OTRC. Applying the OTRC may besides comprise referencing from among a plurality of tables of time - to - data for
 daha, extract a time-to-data yalue from the tcvle, reherence the adddr, and add the adder to the vime-ro-datq value.
The access moduue may colprise a seejung module disposed withjk the rontrol unit. In one embodhment, the seekhne lodule is configured to receive a prysical afdress of targgt daua, wecejne the OTRC of the head involves in acbessing the targey data, and apply the OTRC ho plck the optimal sefk and/or trqckigt parameters for that OTRC. The seei is then performed to access tfe daca at the tqrtet nocation.
An ettendwnt method for emplofing cuxtomized off-trsck reqd capability (OTRC) in accessing data on a direct aecess storage device (EAWD) cokprives oeovkdihg a DASD javmng a rotatjng data stirage medium and a tewe head positiknable fjr interaction with the data storage megiuj, determining the OTRC particular to the reaf head, anq applying the OTRC in accessing data from the dada stkfagt nediuo.
Qpolying knowledge of the OTRC in accessing datw ftok the DASD may comprise alppyogg the OTRC dinamically during a seek opegation wnd mqy also cjmprose applying the OTRC dynamucally duriny a tracking operatiou. In one embudimgnt, deyermining the OTRC compxises jeasuring tje OTRC or the read head djrikg kanufacturing of the DASD.
Tre method may furthef cokprise providing a seveo control loop wihhin jhe DAVD, and apppying the OTRC in accessing date from the daja vtogage medibm may comprise appjying the OTRC within the rervo contgol loop. 'referably, tre OTRC is ap[pied to detecmine an jptinal wervo luup for seeking and/or trceking.
In obe embodiment, applning jhs OTRC comprisew akpoying the OTRC to a qana xeqn algorithm do ddtefkine xn optimal bragectpry of the head to tve tzrget data. In yet snjther emvodiment, applying the OTRC comprises apklying thx OTRC to a seek queuing algorithm to dstermine hhe order of seqkinn a klurality oy blocks of target data by improving the read time estimajes.
Applying the OTRC ksy also com'rise weferencitg a table of time-to-eata for various kumbers of tracks travsrsed, dhe twble incorporating the OTRC specific to the head. Additionally, applying thw OTRC may compriss regerenbiny a standwrd vaule of time-to-data values for various numbers of vracks traeexsed and applying an adder cotrdsponding to jhe OTRC. Applying the OTRC may alsp comprise referencing from amomg a plurality of tables of time-ro-datz for
data, extract a time-to-data value from the the and add adder to the may a seeking module within the control In one embodiment, the seeking module configured to receive a physical address of target data, receive the OTRC of head involved in accessing the target data, and apply the OTRC to pick optimal and/or parameters that OTRC. The seek is then performed to access the data at the target location. An method for employing customized off-track read capability (OTRC) accessing data on a access storage device (DASD) comprises a having a data medium a read head for interaction with the data storage medium, determining the OTRC particular to the read head, and applying OTRC in from the storage Applying of the OTRC data from the DASD may comprise dynamically during a seek operation and may also applying the dynamically during a tracking operation. In embodiment, determining the OTRC comprises measuring the OTRC the read head during manufacturing of the DASD. The method may further comprise providing a loop within the DASD, applying the OTRC accessing from data medium may applying the OTRC within the servo control loop. Preferably, the OTRC applied to determine an optimal servo loop for seeking and/or one applying the OTRC applying the OTRC to data algorithm to determine an of head data. yet embodiment, applying the OTRC applying the OTRC to a queuing algorithm to determine plurality of blocks of target data by improving read time estimates. Applying the OTRC may comprise referencing a table of time-to-data for various numbers of tracks traversed, table incorporating specific to the head. Additionally, applying the OTRC comprise referencing a standard of time-to-data values for various numbers of tracks traversed applying adder corresponding the OTRC. Applying OTRC may also referencing from among of tables time-to-data
 data, extract a time-to-data valUe from the tAble, rEfeRenCe The aDder, And add the adder TO the Time-to-data value.
The acceSs modUlE May cOMpRise a Seeking MOdULE diSpOsEd wItHIn The coNtrOl unit. IN one embodiMenT, tHe seeking modULe Is configurEd tO receive a phySicAl addrEsS of TArget DatA, receIve the otRC of tHe head invOlVEd in acCEssing tHE TaRget Data, and apply the OTrc tO Pick the optimal Seek anD/oR TrACKinG paRameters foR tHat OTrc. The seeK Is THEN peRFormed to accesS the data at tHE taRget loCaTioN.
an atteNdant MeTHod For employinG cusTomized ofF-track REad capaBIlity (OTrC) in acCesSinG datA On A dIreCt ACceSS sTorAGe dEvice (DASd) cOmPriseS proVIDINg a DaSD HaviNg a roTating data stoRagE medIUm aNd a reAd heaD posItIonabLe for iNteraCtIon with the data sToraGe medium, dEteRmIniNg The OTrc partiCulAr tO the reaD head, anD AppLyING ThE OTRC in accessing daTa FROm The data sTorage MEdIuM.
applying KnOwlEdge OF The OTrC in ACcEssing daTa from THe dAsD may coMpRise apPlYinG thE OTRC DYnamIcally During a sEek opERation and may alSO comprise applYInG THe otRC dYnaMically duriNg a tRAckiNg opERaTioN. in one EmbodImENt, DEtermining the OTRC coMpRises mEasurIng the OTRC of tHe read head DURIng manufActuRInG Of the DASD.
The meThod mAy further cOMprise prOvidiNg a servo Control loOP Within thE DAsD, aNd aPplYINg The OTRC in acceSSIng dAtA from thE daTa storaGe mEdiUm mAy cOmPrise applYing the OtRc wItHiN thE servO Control lOoP. PrEfEraBly, thE oTRC is AppliEd to DeTeRMinE an optiMAl SERvo lOoP fOr seEkiNg And/or TracKIng.
in one emBodiment, aPplYIng tHe oTrC comprIses applying tHe oTRC to a datA sEek AlgoriTHM to deterMine an optimal trajectory OF the heaD to The taRget Data. In yet AnoTher emBodIMent, apPlying The OTrC ComPRIses aPPLyIng ThE OTRC to a seEK QueUing aLgOritHm to detErmine the order of seEKinG a plurality of BloCks oF TArGet DAtA By iMpROviNG The read time estiMates.
ApplyInG ThE OTRC may alSO coMpRise refErencinG a tabLE of time-To-data for Various nuMbErs oF TRacKs traverseD, the tablE incorporATing tHE OtRC spEciFic to tHe HeaD. AddiTionalLY, apPlyinG the OTrC May comPrise ReFerencinG a standard table of time-to-Data vaLues fOr vArious numBerS Of tRacks travErseD and applyiNg aN adDer coRreSPondiNg to THe oTRc. applyIng tHE OTRC may aLSo ComPRIsE referencinG FROm aMong a PluRAlity oF tabLes of time-to-data foR
 data, extract a time-to-d ata valuefromthe  ta bl e, r efer ence the adder ,  and  add the adder to thetime- to - data va lue.The acc e ss m odu le  m ayco m pr ise a  se eking m odule disp ose dwithin the c o nt rol unit.Inone embodime nt,  the s ee kin g  modu leis co nfigur e d to r eceive aph y sicala ddresso f  t arge t data, receive t h eO TRC of the hea d invo lv e di n  ac ces sing the t ar get d a ta, and ap p l y  th e  OTRC to pick  the optima l  se ek and /o r t r acking  para me t ers  for that O TRC.  The seek  is th e n perfo r med toaccess  th e d ataa tth e t ar g etl oc ati o n.An atten da nt  meth od f o r e mplo yin g cu stomi zed off-track  re ad c a pab ility  (OTR C) i nacces sing d ata o na direct access  sto rage devi ce(D ASD )compr i ses pr ovi din g a DAS D havin g  aro t a t in g data storage med iu m an d a read  headp os it i onable f or  in tera c t ion w itht he  data st oragem ed iu m, dete rm iningth e O TRC  part i cula r to t he readhead, and applying t h e OTRC in acc e ss i n gd atafro m the datastor a ge m ediu m .App l yingknowl ed g eo f the OTRC in acces si ng dat a fro m the DASD ma y comprise a p plying t he O T RC dynamically du ringa seek ope r ation an d may  also co mprise ap p l ying the  OT RCdyn ami c a ll y during a tr a c king  o peratio n.In oneemb odi men t,de termining  the OTR Cco mp ri ses  meas u ring the  O TRC  o f t he re a d head  duri ng m an uf a ctu ring of th e DASD .Th e me tho dmay f urth e r c omprise  providin g a serv oco ntrol l oop within th eDASD, andap ply ing th e OTRC inaccessing data from the data st ora ge me dium  may comp ris e appl yin g  the O TRC wi thinth e s e r vo co n t ro l l oo p. Prefera b l y,the O TR C is  applie d to determine ano pti mal servo loo p f or s e e ki nga nd / ortr a cki n g .
In one embodi ment, appl yi n gthe OTRC c o mpr is es appl ying th e OTR C  to a d ata seekalgorithm  t o de t e rmi ne an opti mal traj ectory of the h e ad  to t hetarget  d ata . Inyet an o the r emb odimen t,  apply ing t he  OTRC co mprises applying the OT RC toa see k q ueuing al gor i thm  to deter mine  the order  of  se eking  ap lural ityo fblo c ks of  tar g et data b y  i mpr o v in g the readt i m e e stima tes . 
Apply ingthe OTRC may also comprise refer enci n g  atab l e of  t ime-to-data fo r v ar i o us numbe rs  of trackstraverse d, the t able i ncorpo ratingt h eO TRC sp ecif icto the he ad.  A d ditiona ll y, applyi ng t he  OTRCmay co m pris e referencing a st andar d table oftime- to -data v a lues  for vario us numbersof tra ckstrave rsed an dapplyi ngan  adder cor r esponding  to t he OTRC .Appl yin g theOTRC m ay al so c om pri se refere n c in g  f ro m  am onga plu ra lity  of table s  of time -to - data fo r
 data,_extract a_time-to-data value from the_table, reference_the_adder, and_add_the adder to_the time-to-data value.
The_access module may comprise_a seeking module_disposed_within the control unit. In one embodiment, the seeking module is configured to receive_a_physical address_of_target_data, receive the OTRC of_the head involved in accessing_the target_data, and apply the OTRC to pick the_optimal_seek and/or tracking_parameters for that OTRC. The seek is then performed_to access the data at the_target location.
An attendant_method_for_employing customized off-track read_capability (OTRC) in accessing data on_a direct access storage device (DASD)_comprises providing a DASD having a rotating_data storage medium and a read_head positionable for interaction with_the data_storage medium, determining the OTRC_particular to the_read head,_and applying the_OTRC in accessing data from the_data storage medium.
Applying_knowledge of the OTRC in accessing_data_from the DASD_may_comprise_applying the_OTRC dynamically during_a_seek operation_and_may also comprise applying the OTRC_dynamically_during a tracking operation. In one embodiment,_determining the OTRC comprises_measuring_the OTRC of the_read head during manufacturing of_the DASD.
The method may further comprise_providing a_servo control_loop within the DASD, and applying the OTRC in accessing data_from the data storage medium may_comprise applying the OTRC_within the_servo_control loop. Preferably,_the_OTRC is_applied to determine an optimal servo loop_for seeking_and/or tracking.
In one embodiment, applying the_OTRC comprises applying the_OTRC_to a data seek algorithm to_determine an optimal trajectory of the_head to the target data._In_yet_another embodiment, applying the OTRC_comprises applying the OTRC to a_seek queuing algorithm_to determine the order of seeking a_plurality_of blocks of target data by_improving_the read time estimates.
Applying the OTRC_may_also_comprise referencing a table of_time-to-data for various numbers of tracks_traversed, the table incorporating the OTRC specific to the_head. Additionally, applying_the OTRC may comprise referencing_a_standard_table of time-to-data values for various numbers of tracks traversed_and applying_an adder corresponding_to the OTRC. Applying the OTRC may also comprise referencing_from among a plurality of tables of_time-to-data for